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diff --git a/man-pages-posix-2017/man1p/mailx.1p b/man-pages-posix-2017/man1p/mailx.1p new file mode 100644 index 0000000..e3f8fd4 --- /dev/null +++ b/man-pages-posix-2017/man1p/mailx.1p @@ -0,0 +1,3093 @@ +'\" et +.TH MAILX "1P" 2017 "IEEE/The Open Group" "POSIX Programmer's Manual" +.\" +.SH PROLOG +This manual page is part of the POSIX Programmer's Manual. +The Linux implementation of this interface may differ (consult +the corresponding Linux manual page for details of Linux behavior), +or the interface may not be implemented on Linux. +.\" +.SH NAME +mailx +\(em process messages +.SH SYNOPSIS +.SS "Send Mode" +.sp +.RS 4 +.nf + +mailx \fB[\fR-s \fIsubject\fB]\fI address\fR... +.fi +.P +.RE +.SS "Receive Mode" +.sp +.RS 4 +.nf + +mailx -e +.P +mailx \fB[\fR-HiNn\fB] [\fR-F\fB] [\fR-u \fIuser\fB]\fR +.P +mailx -f \fB[\fR-HiNn\fB] [\fR-F\fB] [\fIfile\fB]\fR +.fi +.P +.RE +.SH DESCRIPTION +The +.IR mailx +utility provides a message sending and receiving facility. It has two +major modes, selected by the options used: Send Mode and Receive +Mode. +.P +On systems that do not support the User Portability Utilities option, +an application using +.IR mailx +shall have the ability to send messages in an unspecified manner (Send +Mode). Unless the first character of one or more lines is +<tilde> +(\c +.BR '\(ti' ), +all characters in the input message shall appear in the delivered +message, but additional characters may be inserted in the message +before it is retrieved. +.P +On systems supporting the User Portability Utilities option, +mail-receiving capabilities and other interactive features, Receive +Mode, described below, also shall be enabled. +.SS "Send Mode" +.P +Send Mode can be used by applications or users to send messages from +the text in standard input. +.SS "\*!Receive Mode" +.P +Receive Mode is more oriented towards interactive users. Mail can be read +and sent in this interactive mode. +.P +When reading mail, +.IR mailx +provides commands to facilitate saving, deleting, and responding to +messages. When sending mail, +.IR mailx +allows editing, reviewing, and other modification of the message as it +is entered. +.P +Incoming mail shall be stored in one or more unspecified locations for +each user, collectively called the system +.IR mailbox +for that user. When +.IR mailx +is invoked in Receive Mode, the system mailbox shall be the default +place to find new mail. As messages are read, they shall be marked to +be moved to a secondary file for storage, unless specific action is +taken. This secondary file is called the +.BR mbox +and is normally located in the directory referred to by the +.IR HOME +environment variable (see +.IR MBOX +in the ENVIRONMENT VARIABLES section for a description of this file). +Messages shall remain in this file until explicitly removed. When the +.BR \-f +option is used to read mail messages from secondary files, messages +shall be retained in those files unless specifically removed. All +three of these locations\(emsystem mailbox, +.BR mbox , +and secondary file\(emare referred to in this section as simply +``mailboxes'', unless more specific identification is required. +.SH OPTIONS +The +.IR mailx +utility shall conform to the Base Definitions volume of POSIX.1\(hy2017, +.IR "Section 12.2" ", " "Utility Syntax Guidelines". +.P +The following options shall be supported. (Only the +.BR \-s +.IR subject +option shall be required on all systems. The other options are required +only on systems supporting the User Portability Utilities option.) +.IP "\fB\-e\fP" 10 +Test for the presence of mail in the system mailbox. The +.IR mailx +utility shall write nothing and exit with a successful return code if +there is mail to read. +.IP "\fB\-f\fP" 10 +Read messages from the file named by the +.IR file +operand instead of the system mailbox. (See also +.BR folder .) +If no +.IR file +operand is specified, read messages from +.BR mbox +instead of the system mailbox. +.IP "\fB\-F\fP" 10 +Record the message in a file named after the first recipient. The name +is the login-name portion of the address found first on the +.BR To: +line in the mail header. Overrides the +.BR record +variable, if set (see +.IR "Internal Variables in mailx"). +.IP "\fB\-H\fP" 10 +Write a header summary only. +.IP "\fB\-i\fP" 10 +Ignore interrupts. (See also +.BR ignore .) +.IP "\fB\-n\fP" 10 +Do not initialize from the system default start-up file. See the +EXTENDED DESCRIPTION section. +.IP "\fB\-N\fP" 10 +Do not write an initial header summary. +.IP "\fB\-s\0\fIsubject\fR" 10 +Set the +.BR Subject +header field to +.IR subject . +All characters in the +.IR subject +string shall appear in the delivered message. The results are +unspecified if +.IR subject +is longer than +{LINE_MAX} +\- 10 bytes or contains a +<newline>. +.IP "\fB\-u\0\fIuser\fR" 10 +Read the system mailbox of the login name +.IR user . +This shall only be successful if the invoking user has appropriate +privileges to read the system mailbox of that user. +.SH OPERANDS +The following operands shall be supported: +.IP "\fIaddress\fR" 10 +Addressee of message. When +.BR \-n +is specified and no user start-up files are accessed (see the EXTENDED +DESCRIPTION section), the user or application shall ensure this is an +address to pass to the mail delivery system. Any system or user +start-up files may enable aliases (see +.BR alias +under +.IR "Commands in mailx") +that may modify the form of +.IR address +before it is passed to the mail delivery system. +.IP "\fIfile\fR" 10 +A pathname of a file to be read instead of the system mailbox when +.BR \-f +is specified. The meaning of the +.IR file +option-argument shall be affected by the contents of the +.BR folder +internal variable; see +.IR "Internal Variables in mailx". +.SH STDIN +When +.IR mailx +is invoked in Send Mode (the first synopsis line), standard input shall +be the message to be delivered to the specified addresses. +When in Receive Mode, user commands shall be accepted from +.IR stdin . +If the User Portability Utilities option is not supported, standard +input lines beginning with a +<tilde> +(\c +.BR '\(ti' ) +character produce unspecified results. +.P +If the User Portability Utilities option is supported, then in both +Send and Receive Modes, standard input lines beginning with the escape +character (usually +<tilde> +(\c +.BR '\(ti' )) +shall affect processing as described in +.IR "Command Escapes in mailx". +.SH "INPUT FILES" +When +.IR mailx +is used as described by this volume of POSIX.1\(hy2017, the +.IR file +option-argument (see the +.BR \-f +option) and the +.BR mbox +shall be text files containing mail messages, formatted as described in +the OUTPUT FILES section. The nature of the system mailbox is +unspecified; it need not be a file. +.SH "ENVIRONMENT VARIABLES" +Some of the functionality described in this section shall be provided on +implementations that support the User Portability Utilities option +as described in the text, and is not further shaded for this option. +.P +The following environment variables shall affect the execution of +.IR mailx : +.IP "\fIDEAD\fP" 10 +Determine the pathname of the file in which to save partial messages in +case of interrupts or delivery errors. The default shall be +.BR dead.letter +in the directory named by the +.IR HOME +variable. The behavior of +.IR mailx +in saving partial messages is unspecified if the User Portability +Utilities option is not supported and +.IR DEAD +is not defined with the value +.BR /dev/null . +.IP "\fIEDITOR\fP" 10 +Determine the name of a utility to invoke when the +.BR edit +(see +.IR "Commands in mailx") +or +.BR ~e +(see +.IR "Command Escapes in mailx") +command is used. The default editor is unspecified. +On XSI-conformant systems it is +.IR ed . +The effects of this variable are unspecified if the User Portability +Utilities option is not supported. +.IP "\fIHOME\fP" 10 +Determine the pathname of the user's home directory. +.IP "\fILANG\fP" 10 +Provide a default value for the internationalization variables that are +unset or null. (See the Base Definitions volume of POSIX.1\(hy2017, +.IR "Section 8.2" ", " "Internationalization Variables" +for the precedence of internationalization variables used to determine +the values of locale categories.) +.IP "\fILC_ALL\fP" 10 +If set to a non-empty string value, override the values of all the +other internationalization variables. +.IP "\fILC_CTYPE\fP" 10 +Determine the locale for the interpretation of sequences of bytes of +text data as characters (for example, single-byte as opposed to +multi-byte characters in arguments and input files) and the handling of +case-insensitive address and header-field comparisons. +.IP "\fILC_TIME\fP" 10 +This variable may determine the format and contents of the date and +time strings written by +.IR mailx . +This volume of POSIX.1\(hy2017 specifies the effects of this variable only for systems +supporting the User Portability Utilities option. +.IP "\fILC_MESSAGES\fP" 10 +.br +Determine the locale that should be used to affect the format and +contents of diagnostic messages written to standard error and +informative messages written to standard output. +.IP "\fILISTER\fP" 10 +Determine a string representing the command for writing the contents of +the +.BR folder +directory to standard output when the +.BR folders +command is given (see +.BR folders +in +.IR "Commands in mailx"). +Any string acceptable as a +.IR command_string +operand to the +.IR sh +.BR \-c +command shall be valid. If this variable is null or not set, the output +command shall be +.IR ls . +The effects of this variable are unspecified if the User Portability +Utilities option is not supported. +.IP "\fIMAILRC\fP" 10 +Determine the pathname of the user start-up file. The default shall be +.BR .mailrc +in the directory referred to by the +.IR HOME +environment variable. The behavior of +.IR mailx +is unspecified if the User Portability Utilities option is not +supported and +.IR MAILRC +is not defined with the value +.BR /dev/null . +.IP "\fIMBOX\fP" 10 +Determine a pathname of the file to save messages from the system +mailbox that have been read. The +.BR exit +command shall override this function, as shall saving the message +explicitly in another file. The default shall be +.BR mbox +in the directory named by the +.IR HOME +variable. The effects of this variable are unspecified if the User +Portability Utilities option is not supported. +.IP "\fINLSPATH\fP" 10 +Determine the location of message catalogs for the processing of +.IR LC_MESSAGES . +.IP "\fIPAGER\fP" 10 +Determine a string representing an output filtering or pagination +command for writing the output to the terminal. Any string acceptable +as a +.IR command_string +operand to the +.IR sh +.BR \-c +command shall be valid. When standard output is a terminal device, the +message output shall be piped through the command if the +.IR mailx +internal variable +.BR crt +is set to a value less the number of lines in the message; see +.IR "Internal Variables in mailx". +If the +.IR PAGER +variable is null or not set, the paginator shall be either +.IR more +or another paginator utility documented in the system documentation. +The effects of this variable are unspecified if the User Portability +Utilities option is not supported. +.IP "\fISHELL\fP" 10 +Determine the name of a preferred command interpreter. The default +shall be +.IR sh . +The effects of this variable are unspecified if the User Portability +Utilities option is not supported. +.IP "\fITERM\fP" 10 +If the internal variable +.BR screen +is not specified, determine the name of the terminal type to indicate +in an unspecified manner the number of lines in a screenful of headers. +If +.IR TERM +is not set or is set to null, an unspecified default terminal type +shall be used and the value of a screenful is unspecified. The effects +of this variable are unspecified if the User Portability Utilities +option is not supported. +.IP "\fITZ\fP" 10 +This variable may determine the timezone used to calculate date and +time strings written by +.IR mailx . +If +.IR TZ +is unset or null, an unspecified default timezone shall be used. +.IP "\fIVISUAL\fP" 10 +Determine a pathname of a utility to invoke when the +.BR visual +command (see +.IR "Commands in mailx") +or +.BR ~v +command-escape (see +.IR "Command Escapes in mailx") +is used. If this variable is null or not set, the full-screen editor +shall be +.IR vi . +The effects of this variable are unspecified if the User Portability +Utilities option is not supported. +.SH "ASYNCHRONOUS EVENTS" +When +.IR mailx +is in Send Mode and standard input is not a terminal, it shall take the +standard action for all signals. +.P +In +Receive Mode, or in +Send Mode when standard input is a terminal, if a SIGINT signal +is received: +.IP " 1." 4 +If in command mode, the current command, if there is one, shall be +aborted, and a command-mode prompt shall be written. +.IP " 2." 4 +If in input mode: +.RS 4 +.IP " a." 4 +If +.BR ignore +is set, +.IR mailx +shall write +.BR \(dq@\en\(dq , +discard the current input line, and continue processing, bypassing the +message-abort mechanism described in item 2b. +.IP " b." 4 +If the interrupt was received while sending mail, either when in +Receive Mode or in +Send Mode, a message shall be written, and another +subsequent interrupt, with no other intervening characters typed, shall +be required to abort the mail message. +If in Receive Mode and another +interrupt is received, a command-mode prompt shall be written. +If in Send Mode and another interrupt is received, +.IR mailx +shall terminate with a non-zero status. +.RS 4 +.P +In both cases listed in item b, if the message is not empty: +.IP " i." 5 +If +.BR save +is enabled and the file named by +.IR DEAD +can be created, the message shall be written to the file named by +.IR DEAD . +If the file exists, the message shall be written to replace the +contents of the file. +.IP ii. 5 +If +.BR save +is not enabled, or +the file named by +.IR DEAD +cannot be created, the message shall not be saved. +.RE +.RE +.P +The +.IR mailx +utility shall take the standard action for all other signals. +.SH STDOUT +In command and input modes, all output, including prompts and messages, +shall be written to standard output. +.SH STDERR +The standard error shall be used only for diagnostic messages. +.SH "OUTPUT FILES" +Various +.IR mailx +commands and command escapes can create or add to files, including the +.BR mbox , +the dead-letter file, and secondary mailboxes. When +.IR mailx +is used as described in this volume of POSIX.1\(hy2017, these files shall be text files, +formatted as follows: +.sp +.RS +\fRline beginning with \fBFrom<space> +.br +[\fRone or more \fIheader-lines\fR; see +.IR "Commands in mailx"] +.br +\fIempty line +.br +\fB[\fRzero or more \fIbody lines +.br +\fIempty line] +.br +\fB[\fRline beginning with \fBFrom<space>...]\fR +.RE +.P +where each message begins with the +.BR "From\0<space>" +line shown, preceded by the beginning of the file or an empty line. +(The +.BR "From <space>" +line is considered to be part of the message header, but not one of the +header-lines referred to in +.IR "Commands in mailx"; +thus, it shall not be affected by the +.BR discard , +.BR ignore , +or +.BR retain +commands.) The formats of the remainder of the +.BR "From <space>" +line and any additional header lines are unspecified, except that none +shall be empty. The format of a message body line is also unspecified, +except that no line following an empty line shall start with +.BR "From <space>" ; +.IR mailx +shall modify any such user-entered message body lines (following an +empty line and beginning with +.BR "From <space>" ) +by adding one or more characters to precede the +.BR 'F' ; +it may add these characters to +.BR "From <space>" +lines that are not preceded by an empty line. +.P +When a message from the system mailbox or entered by the user is not a +text file, it is implementation-defined how such a message is stored +in files written by +.IR mailx . +.SH "EXTENDED DESCRIPTION" +The functionality in the entire EXTENDED DESCRIPTION section shall +be provided on implementations supporting the User Portability +Utilities option. +The functionality described in this section shall be provided on +implementations that support the User Portability Utilities option +(and the rest of this section is not further shaded for this option). +.P +The +.IR mailx +utility need not support for all character encodings in all +circumstances. For example, inter-system mail may be restricted to +7-bit data by the underlying network, 8-bit data need not be portable +to non-internationalized systems, and so on. Under these +circumstances, it is recommended that only characters defined in the +ISO/IEC\ 646:\|1991 standard International Reference Version (equivalent to ASCII) 7-bit range +of characters be used. +.P +When +.IR mailx +is invoked using one of the Receive Mode synopsis forms, it shall write +a page of header-summary lines (if +.BR \-N +was not specified and there are messages, see below), followed by a +prompt indicating that +.IR mailx +can accept regular commands (see +.IR "Commands in mailx"); +this is termed +.IR "command mode" . +The page of header-summary lines shall contain the first new message if +there are new messages, or the first unread message if there are unread +messages, or the first message. When +.IR mailx +is invoked using the Send Mode synopsis and standard input is a +terminal, if no subject is specified on the command line and the +.BR asksub +variable is set, a prompt for the subject shall be written. At this +point, +.IR mailx +shall be in input mode. This input mode shall also be entered when using +one of the Receive Mode synopsis forms and a reply or new message is +composed using the +.BR reply , +.BR Reply , +.BR followup , +.BR Followup , +or +.BR mail +commands and standard input is a terminal. When the message is typed +and the end of the message is encountered, the message shall be passed to +the mail delivery software. Commands can be entered by beginning a line +with the escape character (by default, +<tilde> +(\c +.BR '\(ti' )) +followed by a single command letter and optional arguments. See +.IR "Commands in mailx" +for a summary of these commands. It is unspecified what effect these +commands will have if standard input is not a terminal when a message +is entered using either the Send Mode synopsis, or the Read Mode +commands +.BR reply , +.BR Reply , +.BR followup , +.BR Followup , +or +.BR mail . +.TP 10 +.BR Note: +For notational convenience, this section uses the default escape +character, +<tilde>, +in all references and examples. +.P +.P +At any time, the behavior of +.IR mailx +shall be governed by a set of environmental and internal variables. +These are flags and valued parameters that can be set and cleared via +the +.IR mailx +.BR set +and +.BR unset +commands. +.P +Regular commands are of the form: +.sp +.RS 4 +.nf + +\fB[\fIcommand\fB] [\fImsglist\fB] [\fIargument \fR...\fB] +.fi +.P +.RE +.P +If no +.IR command +is specified in command mode, +.BR next +shall be assumed. In input mode, commands shall be recognized by the +escape character, and lines not treated as commands shall be taken as +input for the message. +.P +In command mode, each message shall be assigned a sequential number, +starting with 1. +.P +All messages have a state that shall affect how they are displayed in +the header summary and how they are retained or deleted upon +termination of +.IR mailx . +There is at any time the notion of a +.IR current +message, which shall be marked by a +.BR '>' +at the beginning of a line in the header summary. When +.IR mailx +is invoked using one of the Receive Mode synopsis forms, the current +message shall be the first new message, if there is a new message, or +the first unread message if there is an unread message, or the first +message if there are any messages, or unspecified if there are no +messages in the mailbox. Each command that takes an optional list of +messages (\fImsglist\fP) or an optional single message (\fImessage\fP) +on which to operate shall leave the current message set to the +highest-numbered message of the messages specified, unless the command +deletes messages, in which case the current message shall be set to the +first undeleted message (that is, a message not in the deleted state) +after the highest-numbered message deleted by the command, if one +exists, or the first undeleted message before the highest-numbered +message deleted by the command, if one exists, or to an unspecified +value if there are no remaining undeleted messages. All messages +shall be in one of the following states: +.IP "\fInew\fR" 10 +The message is present in the system mailbox and has not been viewed by +the user or moved to any other state. Messages in state +.IR new +when +.IR mailx +quits shall be retained in the system mailbox. +.IP "\fIunread\fR" 10 +The message has been present in the system mailbox for more than one +invocation of +.IR mailx +and has not been viewed by the user or moved to any other state. +Messages in state +.IR unread +when +.IR mailx +quits shall be retained in the system mailbox. +.IP "\fIread\fR" 10 +The message has been processed by one of the following commands: +.BR ~f , +.BR ~m , +.BR ~F , +.BR ~M , +.BR copy , +.BR mbox , +.BR next , +.BR pipe , +.BR print , +.BR Print , +.BR top , +.BR type , +.BR Type , +.BR undelete . +The +.BR delete , +.BR dp , +and +.BR dt +commands may also cause the next message to be marked as +.IR read , +depending on the value of the +.BR autoprint +variable. Messages that are in the system mailbox and in state +.IR read +when +.IR mailx +quits shall be saved in the +.BR mbox , +unless the internal variable +.BR hold +was set. Messages that are in the +.BR mbox +or in a secondary mailbox and in state +.IR read +when +.IR mailx +quits shall be retained in their current location. +.IP "\fIdeleted\fR" 10 +The message has been processed by one of the following commands: +.BR delete , +.BR dp , +.BR dt . +Messages in state +.IR deleted +when +.IR mailx +quits shall be deleted. Deleted messages shall be ignored until +.IR mailx +quits or changes mailboxes or they are specified to the undelete +command; for example, the message specification /\c +.IR string +shall only search the subject lines of messages that have not yet been +deleted, unless the command operating on the list of messages is +.BR undelete . +No deleted message or deleted message header shall be displayed by any +.IR mailx +command other than +.BR undelete . +.IP "\fIpreserved\fR" 10 +The message has been processed by a +.BR preserve +command. When +.IR mailx +quits, the message shall be retained in its current location. +.IP "\fIsaved\fR" 10 +The message has been processed by one of the following commands: +.BR save +or +.BR write . +If the current mailbox is the system mailbox, and the internal variable +.BR keepsave +is set, messages in the state saved shall be saved to the file +designated by the +.IR MBOX +variable (see the ENVIRONMENT VARIABLES section). If the current +mailbox is the system mailbox, messages in the state +.IR saved +shall be deleted from the current mailbox, when the +.BR quit +or +.BR file +command is used to exit the current mailbox. +.P +The header-summary line for each message shall indicate the state of +the message. +.P +Many commands take an optional list of messages (\c +.IR msglist ) +on which to operate, which defaults to the current message. A +.IR msglist +is a list of message specifications separated by +<blank> +characters, which can include: +.IP "\fRn\fR" 8 +Message number +.IR n . +.IP "\fR+\fR" 8 +The next undeleted message, or the next deleted message for the +.BR undelete +command. +.IP "\fR\-\fR" 8 +The next previous undeleted message, or the next previous deleted +message for the +.BR undelete +command. +.IP "\fR.\fR" 8 +The current message. +.IP "\fR^\fR" 8 +The first undeleted message, or the first deleted message for the +.BR undelete +command. +.IP "\fR$\fR" 8 +The last message. +.IP "\fR*\fR" 8 +All messages. +.IP "\fRn\(hym\fR" 8 +An inclusive range of message numbers. +.IP "\fIaddress\fR" 8 +All messages from +.IR address ; +any address as shown in a header summary shall be matchable in this +form. +.IP "/\fIstring\fR" 8 +All messages with +.IR string +in the subject line (case ignored). +.IP "\fR:c\fR" 8 +All messages of type +.IR c , +where +.IR c +shall be one of: +.RS 8 +.IP "\fRd\fR" 6 +Deleted messages. +.IP "\fRn\fR" 6 +New messages. +.IP "\fRo\fR" 6 +Old messages (any not in state +.IR read +or +.IR new ). +.IP "\fRr\fR" 6 +Read messages. +.IP "\fRu\fR" 6 +Unread messages. +.RE +.P +Other commands take an optional message (\c +.IR message ) +on which to operate, which defaults to the current message. All of the +forms allowed for +.IR msglist +are also allowed for +.IR message , +but if more than one message is specified, only the first shall be +operated on. +.P +Other arguments are usually arbitrary strings whose usage depends on +the command involved. +.SS "Start-Up in mailx" +.P +At start-up time, +.IR mailx +shall take the following steps in sequence: +.IP " 1." 4 +Establish all variables at their stated default values. +.IP " 2." 4 +Process command line options, overriding corresponding default values. +.IP " 3." 4 +Import any of the +.IR DEAD , +.IR EDITOR , +.IR MBOX , +.IR LISTER , +.IR PAGER , +.IR SHELL , +or +.IR VISUAL +variables that are present in the environment, overriding the +corresponding default values. +.IP " 4." 4 +Read +.IR mailx +commands from an unspecified system start-up file, unless the +.BR \-n +option is given, to initialize any internal +.IR mailx +variables and aliases. +.IP " 5." 4 +Process the user start-up file of +.IR mailx +commands named in the user +.IR MAILRC +variable. +.P +Most regular +.IR mailx +commands are valid inside start-up files, the most common use being to +set up initial display options and alias lists. The following commands +shall be invalid in a start-up file: +.BR ! , +.BR edit , +.BR hold , +.BR mail , +.BR preserve , +.BR reply , +.BR Reply , +.BR shell , +.BR visual , +.BR Copy , +.BR followup , +and +.BR Followup . +Any errors in a start-up file shall either cause +.IR mailx +to terminate with a diagnostic message and a non-zero status or to +continue after writing a diagnostic message, ignoring the remainder of +the lines in the file. +.P +A blank line in a start-up file shall be ignored. +.SS "Internal Variables in mailx" +.P +The following variables are internal +.IR mailx +variables. Each internal variable can be set via the +.IR mailx +.BR set +command at any time. The +.BR unset +and +.BR "set\0no" +.IR name +commands can be used to erase variables. +.P +In the following list, variables shown as: +.sp +.RS 4 +.nf + +variable +.fi +.P +.RE +.P +represent Boolean values. Variables shown as: +.sp +.RS 4 +.nf + +variable=\fIvalue\fP +.fi +.P +.RE +.P +shall be assigned string or numeric values. For string values, the +rules in +.IR "Commands in mailx" +concerning filenames and quoting shall also apply. +.P +The defaults specified here may be changed by the unspecified system +start-up file unless the user specifies the +.BR \-n +option. +.IP "\fBallnet\fP" 10 +All network names whose login name components match shall be treated as +identical. This shall cause the +.IR msglist +message specifications to behave similarly. The default shall be +.BR noallnet . +See also the +.BR alternates +command and the +.BR metoo +variable. +.IP "\fBappend\fR" 10 +Append messages to the end of the +.BR mbox +file upon termination instead of placing them at the beginning. The +default shall be +.BR noappend . +This variable shall not affect the +.BR save +command when saving to +.BR mbox . +.IP "\fBask\fR,\0\fBasksub\fR" 10 +Prompt for a subject line on outgoing mail if one is not specified on +the command line with the +.BR \-s +option. The +.BR ask +and +.BR asksub +forms are synonyms; the system shall refer to +.BR asksub +and +.BR noasksub +in its messages, but shall accept +.BR ask +and +.BR noask +as user input to mean +.BR asksub +and +.BR noasksub . +It shall not be possible to set both +.BR ask +and +.BR noasksub , +or +.BR noask +and +.BR asksub . +The default shall be +.BR asksub , +but no prompting shall be done if standard input is not a terminal. +.IP "\fBaskbcc\fR" 10 +Prompt for the blind copy list. The default shall be +.BR noaskbcc . +.IP "\fBaskcc\fR" 10 +Prompt for the copy list. The default shall be +.BR noaskcc . +.IP "\fBautoprint\fR" 10 +Enable automatic writing of messages after +.BR delete +and +.BR undelete +commands. The default shall be +.BR noautoprint . +.IP "\fBbang\fR" 10 +Enable the special-case treatment of +<exclamation-mark> +characters (\c +.BR '!' ) +in escape command lines; see the +.BR escape +command and +.IR "Command Escapes in mailx". +The default shall be +.BR nobang , +disabling the expansion of +.BR '!' +in the +.IR command +argument to the +.BR ~! +command and the +.BR ~<! \c +.IR command +escape. +.IP "\fBcmd\fR=\fIcommand\fR" 10 +.br +Set the default command to be invoked by the +.BR pipe +command. The default shall be +.BR nocmd . +.IP "\fBcrt\fR=\fInumber\fR" 10 +Pipe messages having more than +.IR number +lines through the command specified by the value of the +.IR PAGER +variable. The default shall be +.BR nocrt . +If it is set to null, the value used is implementation-defined. +.IP "\fBdebug\fR" 10 +Enable verbose diagnostics for debugging. Messages are not delivered. +The default shall be +.BR nodebug . +.IP "\fBdot\fR" 10 +When +.BR dot +is set, a +<period> +on a line by itself during message input from a terminal shall also +signify end-of-file (in addition to normal end-of-file). The default +shall be +.BR nodot . +If +.BR ignoreeof +is set (see below), a setting of +.BR nodot +shall be ignored and the +<period> +is the only method to terminate input mode. +.IP "\fBescape\fR=\fIc\fR" 10 +Set the command escape character to be the character +.BR 'c' . +By default, the command escape character shall be +<tilde>. +If +.BR escape +is unset, +<tilde> +shall be used; if it is set to null, command escaping shall be disabled. +.IP "\fBflipr\fR" 10 +Reverse the meanings of the +.BR R +and +.BR r +commands. The default shall be +.BR noflipr . +.IP "\fBfolder\fR=\fIdirectory\fR" 10 +.br +The default directory for saving mail files. User-specified filenames +beginning with a +<plus-sign> +(\c +.BR '\(pl' ) +shall be expanded by preceding the filename with this directory name +to obtain the real pathname. If +.IR directory +does not start with a +<slash> +(\c +.BR '/' ), +the contents of +.IR HOME +shall be prefixed to it. The default shall be +.BR nofolder . +If +.BR folder +is unset or set to null, user-specified filenames beginning with +.BR '\(pl' +shall refer to files in the current directory that begin with the +literal +.BR '\(pl' +character. See also +.BR outfolder +below. The +.BR folder +value need not affect the processing of the files named in +.IR MBOX +and +.IR DEAD . +.IP "\fBheader\fR" 10 +Enable writing of the header summary when entering +.IR mailx +in Receive Mode. The default shall be +.BR header . +.IP "\fBhold\fR" 10 +Preserve all messages that are read in the system mailbox instead of +putting them in the +.BR mbox +save file. The default shall be +.BR nohold . +.IP "\fBignore\fR" 10 +Ignore interrupts while entering messages. The default shall be +.BR noignore . +.IP "\fBignoreeof\fR" 10 +Ignore normal end-of-file during message input. Input can be +terminated only by entering a +<period> +(\c +.BR '.' ) +on a line by itself or by the +.BR ~. +command escape. The default shall be +.BR noignoreeof . +See also +.BR dot +above. +.IP "\fBindentprefix\fR=\fIstring\fR" 10 +.br +A string that shall be added as a prefix to each line that is inserted +into the message by the +.BR ~m +command escape. This variable shall default to one +<tab>. +.IP "\fBkeep\fR" 10 +When a system mailbox, secondary mailbox, or +.BR mbox +is empty, truncate it to zero length instead of removing it. The +default shall be +.BR nokeep . +.IP "\fBkeepsave\fR" 10 +Keep the messages that have been saved from the system mailbox into +other files in the file designated by the variable +.IR MBOX , +instead of deleting them. The default shall be +.BR nokeepsave . +.IP "\fBmetoo\fR" 10 +Suppress the deletion of the login name of the user from the recipient +list when replying to a message or sending to a group. The default +shall be +.BR nometoo . +.IP "\fBonehop\fR" 10 +When responding to a message that was originally sent to several +recipients, the other recipient addresses are normally forced to be +relative to the originating author's machine for the response. This +flag disables alteration of the recipients' addresses, improving +efficiency in a network where all machines can send directly to all +other machines (that is, one hop away). The default shall be +.BR noonehop . +.IP "\fBoutfolder\fR" 10 +Cause the files used to record outgoing messages to be located in the +directory specified by the +.BR folder +variable unless the pathname is absolute. The default shall be +.BR nooutfolder . +See the +.BR record +variable. +.IP "\fBpage\fR" 10 +Insert a +<form-feed> +after each message sent through the pipe created by the +.BR pipe +command. The default shall be +.BR nopage . +.IP "\fBprompt\fR=\fIstring\fR" 10 +.br +Set the command-mode prompt to +.IR string . +If +.IR string +is null or if +.BR noprompt +is set, no prompting shall occur. The default shall be to prompt with +the string +.BR \(dq?\0\(dq . +.IP "\fBquiet\fR" 10 +Refrain from writing the opening message and version when entering +.IR mailx . +The default shall be +.BR noquiet . +.IP "\fBrecord\fR=\fIfile\fR" 10 +Record all outgoing mail in the file with the pathname +.IR file . +The default shall be +.BR norecord . +See also +.BR outfolder +above. +.IP "\fBsave\fR" 10 +Enable saving of messages in the dead-letter file on interrupt or +delivery error. See the variable +.IR DEAD +for the location of the dead-letter file. The default shall be +.BR save . +.IP "\fBscreen\fR=\fInumber\fR" 10 +.br +Set the number of lines in a screenful of headers for the +.BR headers +and +.BR z +commands. If +.BR screen +is not specified, a value based on the terminal type identified by the +.IR TERM +environment variable, the window size, the baud rate, or some +combination of these shall be used. +.IP "\fBsendwait\fR" 10 +Wait for the background mailer to finish before returning. The default +shall be +.BR nosendwait . +.IP "\fBshowto\fR" 10 +When the sender of the message was the user who is invoking +.IR mailx , +write the information from the +.BR To: +line instead of the +.BR From: +line in the header summary. The default shall be +.BR noshowto . +.IP "\fBsign\fR=\fIstring\fR" 10 +Set the variable inserted into the text of a message when the +.BR ~a +command escape is given. The default shall be +.BR nosign . +The character sequences +.BR '\et' +and +.BR '\en' +shall be recognized in the variable as +<tab> +and +<newline> +characters, respectively. (See also +.BR ~i +in +.IR "Command Escapes in mailx".) +.IP "\fBSign\fR=\fIstring\fR" 10 +Set the variable inserted into the text of a message when the +.BR ~A +command escape is given. The default shall be +.BR noSign . +The character sequences +.BR '\et' +and +.BR '\en' +shall be recognized in the variable as +<tab> +and +<newline> +characters, respectively. +.IP "\fBtoplines\fR=\fInumber\fR" 10 +.br +Set the number of lines of the message to write with the +.BR top +command. The default shall be 5. +.SS "Commands in mailx" +.P +The following +.IR mailx +commands shall be provided. In the following list, header refers to +lines from the message header, as shown in the OUTPUT FILES section. +Header-line refers to lines within the header that begin with one or +more non-white-space characters, immediately followed by a +<colon> +and white space and continuing until the next line beginning with a +non-white-space character or an empty line. Header-field refers to the +portion of a header line prior to the first +<colon> +in that line. +.P +For each of the commands listed below, the command can be entered as +the abbreviation (those characters in the Synopsis command word +preceding the +.BR '[' ), +the full command (all characters shown for the command word, omitting +the +.BR '[' +and +.BR ']' ), +or any truncation of the full command down to the abbreviation. For +example, the +.BR exit +command (shown as \fBex[it]\fR in the Synopsis) can be entered as +.BR ex , +.BR exi , +or +.BR exit . +.P +The arguments to commands can be quoted, using the following methods: +.IP " *" 4 +An argument can be enclosed between paired double-quotes (\c +.BR \(dq\^\(dq ) +or single-quotes (\c +.BR '\^' ); +any white space, shell word expansion, or +<backslash> +characters within the quotes shall be treated literally as part of the +argument. A double-quote shall be treated literally within single-quotes +and \fIvice versa\fP. These special properties of the +<quotation-mark> +characters shall occur only when they are paired at the beginning and +end of the argument. +.IP " *" 4 +A +<backslash> +outside of the enclosing quotes shall be discarded and the following +character treated literally as part of the argument. +.IP " *" 4 +An unquoted +<backslash> +at the end of a command line shall be discarded and the next line shall +continue the command. +.br +.P +Filenames, where expected, shall be subjected to the following +transformations, in sequence: +.IP " *" 4 +If the filename begins with an unquoted +<plus-sign>, +and the +.BR folder +variable is defined (see the +.BR folder +variable), the +<plus-sign> +shall be replaced by the value of the +.BR folder +variable followed by a +<slash>. +If the +.BR folder +variable is unset or is set to null, the filename shall be unchanged. +.IP " *" 4 +Shell word expansions shall be applied to the filename (see +.IR "Section 2.6" ", " "Word Expansions"). +If more than a single pathname results from this expansion and the +command is expecting one file, the effects are unspecified. +.SS "Declare Aliases" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +a\fB[\fRlias\fB] [\fIalias \fB[\fIaddress\fR...\fB]]\fR +g\fB[\fRroup\fB] [\fIalias \fB[\fIaddress\fR...\fB]]\fR +.fi +.P +.RE +.RE +.P +Add the given addresses to the alias specified by +.IR alias . +The names shall be substituted when +.IR alias +is used as a recipient address specified by the user in an outgoing +message (that is, other recipients addressed indirectly through the +.BR reply +command shall not be substituted in this manner). Mail address alias +substitution shall apply only when the alias string is used as a full +address; for example, when +.BR hlj +is an alias, +.IR hlj@posix.com +does not trigger the alias substitution. If no arguments are given, +write a listing of the current aliases to standard output. If only an +.IR alias +argument is given, write a listing of the specified alias to standard +output. These listings need not reflect the same order of addresses +that were entered. +.SS "Declare Alternatives" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +alt\fB[\fRernates\fB] \fIname\fR... +.fi +.P +.RE +.RE +.P +(See also the +.BR metoo +variable.) Declare a list of alternative names for the user's login. +When responding to a message, these names shall be removed from the +list of recipients for the response. The comparison of names shall be +in a case-insensitive manner. With no arguments, +.BR alternates +shall write the current list of alternative names. +.SS "Change Current Directory" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +cd \fB[\fIdirectory\fB]\fR +ch\fB[\fRdir\fB] [\fIdirectory\fB]\fR +.fi +.P +.RE +.RE +.P +Change directory. If +.IR directory +is not specified, the contents of +.IR HOME +shall be used. +.SS "Copy Messages" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +c\fB[\fRopy\fB] [\fIfile\fB]\fR +c\fB[\fRopy\fB] [\fImsglist\fB] \fIfile\fR +C\fB[\fRopy\fB] [\fImsglist\fB]\fR +.fi +.P +.RE +.RE +.P +Copy messages to the file named by the pathname +.IR file +without marking the messages as saved. Otherwise, it shall be +equivalent to the +.BR save +command. +.P +In the capitalized form, save the specified messages in a file whose +name is derived from the author of the message to be saved, without +marking the messages as saved. Otherwise, it shall be equivalent to +the +.BR Save +command. +.SS "Delete Messages" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +d\fB[\fRelete\fB] [\fImsglist\fB]\fR +.fi +.P +.RE +.RE +.P +Mark messages for deletion from the mailbox. The deletions shall not +occur until +.IR mailx +quits (see the +.BR quit +command) or changes mailboxes (see the +.BR folder +command). If +.BR autoprint +is set and there are messages remaining after the +.BR delete +command, the current message shall be written as described for the +.BR print +command (see the +.BR print +command); otherwise, the +.IR mailx +prompt shall be written. +.SS "Discard Header Fields" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +di\fB[\fRscard\fB] [\fIheader-field\fR...\fB]\fR +ig\fB[\fRnore\fB] [\fIheader-field\fR...\fB]\fR +.fi +.P +.RE +.RE +.P +Suppress the specified header fields when writing messages. Specified +.IR header-fields +shall be added to the list of suppressed header fields. Examples of +header fields to ignore are +.BR status +and +.BR cc . +The fields shall be included when the message is saved. The +.BR Print +and +.BR Type +commands shall override this command. The comparison of header fields +shall be in a case-insensitive manner. If no arguments are specified, +write a list of the currently suppressed header fields to standard +output; the listing need not reflect the same order of header fields +that were entered. +.P +If both +.BR retain +and +.BR discard +commands are given, +.BR discard +commands shall be ignored. +.SS "Delete Messages and Display" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +dp \fB[\fImsglist\fB]\fR +dt \fB[\fImsglist\fB]\fR +.fi +.P +.RE +.RE +.P +Delete the specified messages as described for the +.BR delete +command, except that the +.BR autoprint +variable shall have no effect, and the current message shall be written +only if it was set to a message after the last message deleted by the +command. Otherwise, an informational message to the effect that there +are no further messages in the mailbox shall be written, followed by +the +.IR mailx +prompt. +.SS "Echo a String" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +ec\fB[\fRho\fB] \fIstring\fR ... +.fi +.P +.RE +.RE +.P +Echo the given strings, equivalent to the shell +.IR echo +utility. +.SS "Edit Messages" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +e\fB[\fRdit\fB] [\fImsglist\fB]\fR +.fi +.P +.RE +.RE +.P +Edit the given messages. The messages shall be placed in a temporary +file and the utility named by the +.IR EDITOR +variable is invoked to edit each file in sequence. The default +.IR EDITOR +is unspecified. +.P +The +.BR edit +command does not modify the contents of those messages in the mailbox. +.SS "Exit" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +ex\fB[\fRit\fB]\fR +x\fB[\fRit\fB]\fR +.fi +.P +.RE +.RE +.P +Exit from +.IR mailx +without changing the mailbox. No messages shall be saved in the +.BR mbox +(see also +.BR quit ). +.SS "Change Folder" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +fi\fB[\fRle\fB] [\fIfile\fB]\fR +fold\fB[\fRer\fB] [\fIfile\fB]\fR +.fi +.P +.RE +.RE +.P +Quit (see the +.BR quit +command) from the current file of messages and read in the file named +by the pathname +.IR file . +If no argument is given, the name and status of the current mailbox +shall be written. +.P +Several unquoted special characters shall be recognized when used as +.IR file +names, with the following substitutions: +.IP "\fR%\fR" 8 +The system mailbox for the invoking user. +.IP "\fR%\fIuser\fR" 8 +The system mailbox for +.IR user . +.IP "\fR#\fR" 8 +The previous file. +.IP "\fR&\fR" 8 +The current +.BR mbox . +.IP "\fR+\fIfile\fR" 8 +The named file in the +.BR folder +directory. (See the +.BR folder +variable.) +.P +The default file shall be the current mailbox. +.SS "Display List of Folders" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +\fRfolders\fR +.fi +.P +.RE +.RE +.P +Write the names of the files in the directory set by the +.BR folder +variable. The command specified by the +.IR LISTER +environment variable shall be used (see the ENVIRONMENT VARIABLES +section). +.SS "Follow Up Specified Messages" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +fo\fB[\fRllowup\fB] [\fImessage\fB]\fR +F\fB[\fRollowup\fB] [\fImsglist\fB]\fR +.fi +.P +.RE +.RE +.P +In the lowercase form, respond to a message, recording the response in +a file whose name is derived from the author of the message. See also +the +.BR save +and +.BR copy +commands and +.BR outfolder . +.P +In the capitalized form, respond to the first message in the +.IR msglist , +sending the message to the author of each message in the +.IR msglist . +The subject line shall be taken from the first message and the response +shall be recorded in a file whose name is derived from the author of +the first message. See also the +.BR Save +and +.BR Copy +commands and +.BR outfolder . +.P +Both forms shall override the +.BR record +variable, if set. +.SS "Display Header Summary for Specified Messages" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +f\fB[\fRrom\fB] [\fImsglist\fB]\fR +.fi +.P +.RE +.RE +.P +Write the header summary for the specified messages. +.SS "Display Header Summary" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +h\fB[\fReaders\fB] [\fImessage\fB]\fR +.fi +.P +.RE +.RE +.P +Write the page of headers that includes the message specified. If the +.IR message +argument is not specified, the current message shall not change. +However, if the +.IR message +argument is specified, the current message shall become the message +that appears at the top of the page of headers that includes the +message specified. The +.BR screen +variable sets the number of headers per page. See also the +.BR z +command. +.SS "Help" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +hel\fB[\fRp\fB]\fR +? +.fi +.P +.RE +.RE +.P +Write a summary of commands. +.SS "Hold Messages" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +ho\fB[\fRld\fB] [\fImsglist\fB]\fR +pre\fB[\fRserve\fB] [\fImsglist\fB]\fR +.fi +.P +.RE +.RE +.P +Mark the messages in +.IR msglist +to be retained in the mailbox when +.IR mailx +terminates. This shall override any commands that might previously +have marked the messages to be deleted. During the current invocation +of +.IR mailx , +only the +.BR delete , +.BR dp , +or +.BR dt +commands shall remove the +.IR preserve +marking of a message. +.SS "Execute Commands Conditionally" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +i\fB[\fRf\fB]\fR s|r +\fImail-command\fRs +el\fB[\fRse\fB] +\fImail-command\fRs +en\fB[\fRdif\fB]\fR +.fi +.P +.RE +.RE +.P +Execute commands conditionally, where +.BR "if\0s" +executes the following +.IR mail-command s, +up to an +.BR else +or +.BR endif , +if the program is in Send Mode, and +.BR "if\0r" +shall cause the +.IR mail-command s +to be executed only in Receive Mode. +.SS "List Available Commands" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +l\fB[\fRist\fB]\fR +.fi +.P +.RE +.RE +.P +Write a list of all commands available. No explanation shall be +given. +.SS "Mail a Message" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +m\fB[\fRail\fB] \fIaddress\fR... +.fi +.P +.RE +.RE +.P +Mail a message to the specified addresses or aliases. +.SS "Direct Messages to mbox" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +mb\fB[\fRox\fB] [\fImsglist\fB]\fR +.fi +.P +.RE +.RE +.P +Arrange for the given messages to end up in the +.BR mbox +save file when +.IR mailx +terminates normally. See +.IR MBOX . +See also the +.BR exit +and +.BR quit +commands. +.SS "Process Next Specified Message" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +n\fB[\fRext\fB] [\fImessage\fB]\fR +.fi +.P +.RE +.RE +.P +If the current message has not been written (for example, by the +.BR print +command) since +.IR mailx +started or since any other message was the current message, behave as +if the +.BR print +command was entered. Otherwise, if there is an undeleted message after +the current message, make it the current message and behave as if the +.BR print +command was entered. Otherwise, an informational message to the effect +that there are no further messages in the mailbox shall be written, +followed by the +.IR mailx +prompt. Should the current message location be the result of an +immediately preceding +.BR hold , +.BR mbox , +.BR preserve , +or +.BR touch +command, +.BR next +will act as if the current message has already been written. +.SS "Pipe Message" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +pi\fB[\fRpe\fB] [[\fImsglist\fB] \fIcommand\fB]\fR +| \fB[[\fImsglist\fB] \fIcommand\fB]\fR +.fi +.P +.RE +.RE +.P +Pipe the messages through the given +.IR command +by invoking the command interpreter specified by +.IR SHELL +with two arguments: +.BR \-c +and +.IR command . +(See also +.IR sh +.BR \-c .) +The application shall ensure that the command is given as a single +argument. Quoting, described previously, can be used to accomplish +this. If no arguments are given, the current message shall be piped +through the command specified by the value of the +.BR cmd +variable. If the +.BR page +variable is set, a +<form-feed> +shall be inserted after each message. +.SS "Display Message with Headers" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +P\fB[\fRrint\fB] [\fImsglist\fB]\fR +T\fB[\fRype\fB] [\fImsglist\fB]\fR +.fi +.P +.RE +.RE +.P +Write the specified messages, including all header lines, to standard +output. Override suppression of lines by the +.BR discard , +.BR ignore , +and +.BR retain +commands. If +.BR crt +is set, the messages longer than the number of lines specified by the +.BR crt +variable shall be paged through the command specified by the +.IR PAGER +environment variable. +.SS "Display Message" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +p\fB[\fRrint\fB] [\fImsglist\fB]\fR +t\fB[\fRype\fB] [\fImsglist\fB]\fR +.fi +.P +.RE +.RE +.P +Write the specified messages to standard output. If +.BR crt +is set, the messages longer than the number of lines specified by the +.BR crt +variable shall be paged through the command specified by the +.IR PAGER +environment variable. +.SS "Quit" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +q\fB[\fRuit\fB] +\fIend-of-file\fR +.fi +.P +.RE +.RE +.P +Terminate +.IR mailx , +storing messages that were read in +.BR mbox +(if the current mailbox is the system mailbox and unless +.BR hold +is set), deleting messages that have been explicitly saved (unless +.BR keepsave +is set), discarding messages that have been deleted, and saving all +remaining messages in the mailbox. +.SS "Reply to a Message List" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +R\fB[\fReply\fB] [\fImsglist\fB]\fR +R\fB[\fRespond\fB] [\fImsglist\fB]\fR +.fi +.P +.RE +.RE +.P +Mail a reply message to the sender of each message in the +.IR msglist . +The subject line shall be formed by concatenating +.BR Re: \c +<space> +(unless it already begins with that string) and the subject from the +first message. If +.BR record +is set to a filename, the response shall be saved at the end of that +file. +.P +See also the +.BR flipr +variable. +.SS "Reply to a Message" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +r\fB[\fReply\fB] [\fImessage\fB]\fR +r\fB[\fRespond\fB] [\fImessage\fB]\fR +.fi +.P +.RE +.RE +.P +Mail a reply message to all recipients included in the header of the +message. The subject line shall be formed by concatenating +.BR Re: \c +<space> +(unless it already begins with that string) and the subject from the +message. If +.BR record +is set to a filename, the response shall be saved at the end of that +file. +.P +See also the +.BR flipr +variable. +.SS "Retain Header Fields" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +ret\fB[\fRain\fB] [\fIheader-field\fR...\fB]\fR +.fi +.P +.RE +.RE +.P +Retain the specified header fields when writing messages. This command +shall override all +.BR discard +and +.BR ignore +commands. The comparison of header fields shall be in a +case-insensitive manner. If no arguments are specified, write a list +of the currently retained header fields to standard output; the listing +need not reflect the same order of header fields that were entered. +.SS "Save Messages" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +s\fB[\fRave\fB] [\fIfile\fB]\fR +s\fB[\fRave\fB] [\fImsglist\fB] \fIfile\fR +S\fB[\fRave\fB] [\fImsglist\fB]\fR +.fi +.P +.RE +.RE +.P +Save the specified messages in the file named by the pathname +.IR file , +or the +.BR mbox +if the +.IR file +argument is omitted. The file shall be created if it does not exist; +otherwise, the messages shall be appended to the file. The message +shall be put in the state +.IR saved , +and shall behave as specified in the description of the +.IR saved +state when the current mailbox is exited by the +.BR quit +or +.BR file +command. +.P +In the capitalized form, save the specified messages in a file whose +name is derived from the author of the first message. The name of the +file shall be taken to be the author's name with all network addressing +stripped off. See also the +.BR Copy , +.BR followup , +and +.BR Followup +commands and +.BR outfolder +variable. +.SS "Set Variables" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +se\fB[\fRt\fB] [\fIname\fB[\fR=\fB[\fIstring\fB]] \fR...\fB] [\fIname\fR=\fInumber \fR...\fB] [\fRno\fIname \fR...\fB]\fR +.fi +.P +.RE +.RE +.P +Define one or more variables called +.IR name . +The variable can be given a null, string, or numeric value. Quoting and +<backslash>-escapes +can occur anywhere in +.IR string , +as described previously, as if the +.IR string +portion of the argument were the entire argument. The forms +.IR name +and +.IR name = +shall be equivalent to +.IR name ="" +for variables that take string values. The +.BR set +command without arguments shall write a list of all defined variables +and their values. The +.BR no +.IR name +form shall be equivalent to +.BR unset +.IR name . +.SS "Invoke a Shell" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +sh\fB[\fRell\fB]\fR +.fi +.P +.RE +.RE +.P +Invoke an interactive command interpreter (see also +.IR SHELL ). +.SS "Display Message Size" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +si\fB[\fRze\fB] [\fImsglist\fB]\fR +.fi +.P +.RE +.RE +.P +Write the size in bytes of each of the specified messages. +.SS "Read mailx Commands From a File" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +so\fB[\fRurce\fB] \fIfile\fR +.fi +.P +.RE +.RE +.P +Read and execute commands from the file named by the pathname +.IR file +and return to command mode. +.SS "Display Beginning of Messages" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +to\fB[\fRp\fB] [\fImsglist\fB]\fR +.fi +.P +.RE +.RE +.P +Write the top few lines of each of the specified messages. If the +.BR toplines +variable is set, it is taken as the number of lines to write. The +default shall be 5. +.SS "Touch Messages" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +tou\fB[\fRch\fB] [\fImsglist\fB]\fR +.fi +.P +.RE +.RE +.P +Touch the specified messages. If any message in +.IR msglist +is not specifically deleted nor saved in a file, it shall be placed in +the +.BR mbox +upon normal termination. See +.BR exit +and +.BR quit . +.SS "Delete Aliases" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +una\fB[\fRlias\fB] [\fIalias\fB]\fR... +.fi +.P +.RE +.RE +.P +Delete the specified alias names. If a specified alias does not exist, +the results are unspecified. +.SS "Undelete Messages" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +u\fB[\fRndelete\fB] [\fImsglist\fB]\fR +.fi +.P +.RE +.RE +.P +Change the state of the specified messages from deleted to read. If +.BR autoprint +is set, the last message of those restored shall be written. If +.IR msglist +is not specified, the message shall be selected as follows: +.IP " *" 4 +If there are any deleted messages that follow the current message, the +first of these shall be chosen. +.IP " *" 4 +Otherwise, the last deleted message that also precedes the current +message shall be chosen. +.SS "Unset Variables" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +uns\fB[\fRet\fB] \fIname\fR... +.fi +.P +.RE +.RE +.P +Cause the specified variables to be erased. +.SS "Edit Message with Full-Screen Editor" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +v\fB[\fRisual\fB] [\fImsglist\fB]\fR +.fi +.P +.RE +.RE +.P +Edit the given messages with a screen editor. Each message shall be +placed in a temporary file, and the utility named by the +.IR VISUAL +variable shall be invoked to edit each file in sequence. The default +editor shall be +.IR vi . +.P +The +.BR visual +command does not modify the contents of those messages in the mailbox. +.SS "Write Messages to a File" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +w\fB[\fRrite\fB] [\fImsglist\fB] \fIfile\fR +.fi +.P +.RE +.RE +.P +Write the given messages to the file specified by the pathname +.IR file , +minus the message header. Otherwise, it shall be equivalent to the +.BR save +command. +.SS "Scroll Header Display" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +z\fB[\fR+|-\fB]\fR +.fi +.P +.RE +.RE +.P +Scroll the header display forward (if +.BR '\(pl' +is specified or if no option is specified) or backward (if +.BR '\-' +is specified) one screenful. The number of headers written shall be +set by the +.BR screen +variable. +.SS "Invoke Shell Command" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +!\fIcommand\fR +.fi +.P +.RE +.RE +.P +Invoke the command interpreter specified by +.IR SHELL +with two arguments: +.BR \-c +and +.IR command . +(See also +.IR sh +.BR \-c .) +If the +.BR bang +variable is set, each unescaped occurrence of +.BR '!' +in +.IR command +shall be replaced with the command executed by the previous +.BR ! +command or +.BR ~! +command escape. +.SS "Null Command" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + +# \fIcomment\fR +.fi +.P +.RE +.RE +.P +This null command (comment) shall be ignored by +.IR mailx . +.SS "Display Current Message Number" +.IP "\fISynopsis\fR:" 10 +.sp -1v +.RS 10 +.sp +.RS 4 +.nf + += +.fi +.P +.RE +.RE +.P +Write the current message number. +.SS "Command Escapes in mailx" +.P +The following commands can be entered only from input mode, by +beginning a line with the escape character (by default, +<tilde> +(\c +.BR '\(ti' )). +See the +.BR escape +variable description for changing this special character. The format +for the commands shall be: +.sp +.RS 4 +.nf + +<\fIescape-character\fR><\fIcommand-char\fR><\fIseparator\fR>\fB[\fR<\fIarguments\fR>\fB]\fR +.fi +.P +.RE +.P +where the <\fIseparator\fP> can be zero or more +<blank> +characters. +.P +In the following descriptions, the application shall ensure that the +argument +.IR command +(but not +.IR mailx-command) +is a shell command string. Any string acceptable to the command +interpreter specified by the +.IR SHELL +variable when it is invoked as +.IR SHELL +.BR \-c +.IR command_string +shall be valid. The command can be presented as multiple arguments +(that is, quoting is not required). +.P +Command escapes that are listed with +.IR msglist +or +.IR mailx-command +arguments are invalid in Send Mode and produce unspecified results. +.IP "\fB~!\0\fIcommand\fR" 10 +Invoke the command interpreter specified by +.IR SHELL +with two arguments: +.BR \-c +and +.IR command ; +and then return to input mode. If the +.BR bang +variable is set, each unescaped occurrence of +.BR '!' +in +.IR command +shall be replaced with the command executed by the previous +.BR ! +command or +.BR ~! +command escape. +.IP "\fB~.\fR" 10 +Simulate end-of-file (terminate message input). +.IP "\fB~:\0\fImailx-command\fR,\0\fB~_\0\fImailx-command\fR" 10 +.br +Perform the command-level request. +.IP "\fB~?\fR" 10 +Write a summary of command escapes. +.IP "\fB~A\fR" 10 +This shall be equivalent to +.BR "~i\0Sign" . +.IP "\fB~a\fR" 10 +This shall be equivalent to +.BR "~i\0sign" . +.IP "\fB~b\0\fIname\fR.\|.\|." 10 +Add the +.IR name s +to the blind carbon copy (\c +.BR Bcc ) +list. +.IP "\fB~c\0\fIname\fR.\|.\|." 10 +Add the +.IR name s +to the carbon copy (\c +.BR Cc ) +list. +.IP "\fB~d\fR" 10 +Read in the dead-letter file. See +.IR DEAD +for a description of this file. +.IP "\fB~e\fR" 10 +Invoke the editor, as specified by the +.IR EDITOR +environment variable, on the partial message. +.IP "\fB~f\0[\fImsglist\fB]\fR" 10 +Forward the specified messages. The specified messages shall be +inserted into the current message without alteration. This command +escape also shall insert message headers into the message with field +selection affected by the +.BR discard , +.BR ignore , +and +.BR retain +commands. +.IP "\fB~F\0[\fImsglist\fB]\fR" 10 +This shall be the equivalent of the +.BR ~f +command escape, except that all headers shall be included in the +message, regardless of previous +.BR discard , +.BR ignore , +and +.BR retain +commands. +.IP "\fB~h\fR" 10 +If standard input is a terminal, prompt for a +.BR Subject +line and the +.BR To , +.BR Cc , +and +.BR Bcc +lists. Other implementation-defined headers may also be presented +for editing. If the field is written with an initial value, it can be +edited as if it had just been typed. +.IP "\fB~i\0\fIstring\fR" 10 +Insert the value of the named variable, followed by a +<newline>, +into the text of the message. If the string is unset or null, the +message shall not be changed. +.IP "\fB~m\0[\fImsglist\fB]\fR" 10 +Insert the specified messages into the message, prefixing non-empty +lines with the string in the +.BR indentprefix +variable. This command escape also shall insert message headers into +the message, with field selection affected by the +.BR discard , +.BR ignore , +and +.BR retain +commands. +.IP "\fB~M\0[\fImsglist\fB]\fR" 10 +This shall be the equivalent of the +.BR ~m +command escape, except that all headers shall be included in the +message, regardless of previous +.BR discard , +.BR ignore , +and +.BR retain +commands. +.IP "\fB~p\fR" 10 +Write the message being entered. If the message is longer than +.BR crt +lines (see +.IR "Internal Variables in mailx"), +the output shall be paginated as described for the +.IR PAGER +variable. +.IP "\fB~q\fR" 10 +Quit (see the +.BR quit +command) from input mode by simulating an interrupt. If the body of +the message is not empty, the partial message shall be saved in the +dead-letter file. See +.IR DEAD +for a description of this file. +.IP "\fB~r\0\fIfile\fR,\0\fB~<\0\fIfile\fR,\0\fB~r\0!\fIcommand\fR,\0\fB~<\0!\fIcommand\fR" 10 +.br +Read in the file specified by the pathname +.IR file . +If the argument begins with an +<exclamation-mark> +(\c +.BR '!' ), +the rest of the string shall be taken as an arbitrary system command; +the command interpreter specified by +.IR SHELL +shall be invoked with two arguments: +.BR \-c +and +.IR command . +The standard output of +.IR command +shall be inserted into the message. +.IP "\fB~s\0\fIstring\fR" 10 +Set the subject line to +.IR string . +.IP "\fB~t\0\fIname\fR.\|.\|." 10 +Add the given +.IR name s +to the +.BR To +list. +.IP "\fB~v\fR" 10 +Invoke the full-screen editor, as specified by the +.IR VISUAL +environment variable, on the partial message. +.IP "\fB~w\0\fIfile\fR" 10 +Write the partial message, without the header, onto the file named by +the pathname +.IR file . +The file shall be created or the message shall be appended to it if the +file exists. +.IP "\fB~x\fR" 10 +Exit as with +.BR ~q , +except the message shall not be saved in the dead-letter file. +.IP "\fB~|\0\fIcommand\fR" 10 +Pipe the body of the message through the given +.IR command +by invoking the command interpreter specified by +.IR SHELL +with two arguments: +.BR \-c +and +.IR command . +If the +.IR command +returns a successful exit status, the standard output of the command +shall replace the message. Otherwise, the message shall remain +unchanged. If the +.IR command +fails, an error message giving the exit status shall be written. +.br +.SH "EXIT STATUS" +When the +.BR \-e +option is specified, the following exit values are returned: +.IP "\00" 6 +Mail was found. +.IP >0 6 +Mail was not found or an error occurred. +.P +Otherwise, the following exit values are returned: +.IP "\00" 6 +Successful completion; note that this status implies that all messages +were +.IR sent , +but it gives no assurances that any of them were actually +.IR delivered . +.IP >0 6 +An error occurred. +.SH "CONSEQUENCES OF ERRORS" +When in +input mode (Receive Mode) +or Send Mode: +.IP " *" 4 +If an error is encountered processing an input line beginning +with a +<tilde> +(\c +.BR '\(ti' ) +character, +(see +.IR "Command Escapes in mailx"), +a diagnostic message shall be written to standard error, and the +message being composed may be modified, but this condition shall not +prevent the message from being sent. +.IP " *" 4 +Other errors shall prevent the sending of the message. +.P +When in command mode: +.IP " *" 4 +Default. +.LP +.IR "The following sections are informative." +.SH "APPLICATION USAGE" +Delivery of messages to remote systems requires the existence of +communication paths to such systems. These need not exist. +.P +Input lines are limited to +{LINE_MAX} +bytes, but mailers between systems may impose more severe line-length +restrictions. This volume of POSIX.1\(hy2017 does not place any restrictions on the length of +messages handled by +.IR mailx , +and for delivery of local messages the only limitations should be the +normal problems of available disk space for the target mail file. When +sending messages to external machines, applications are advised to +limit messages to less than 100\|000 bytes because some mail gateways +impose message-length restrictions. +.P +The format of the system mailbox is intentionally unspecified. Not all +systems implement system mailboxes as flat files, particularly with the +advent of multimedia mail messages. Some system mailboxes may be +multiple files, others records in a database. The internal format of +the messages themselves is specified with the historical format from +Version\ 7, but only after the messages have been saved in some file +other than the system mailbox. This was done so that many historical +applications expecting text-file mailboxes are not broken. +.P +Some new formats for messages can be expected in the future, probably +including binary data, bit maps, and various multimedia objects. As +described here, +.IR mailx +is not prohibited from handling such messages, but it must store them +as text files in secondary mailboxes (unless some extension, such as a +variable or command line option, is used to change the stored format). +Its method of doing so is implementation-defined and might include +translating the data into text file-compatible or readable form or +omitting certain portions of the message from the stored output. +.P +The +.BR discard +and +.BR ignore +commands are not inverses of the +.BR retain +command. The +.BR retain +command discards all header-fields except those explicitly retained. +The +.BR discard +command keeps all header-fields except those explicitly discarded. If +headers exist on the retained header list, +.BR discard +and +.BR ignore +commands are ignored. +.SH EXAMPLES +None. +.SH RATIONALE +The standard developers felt strongly that a method for applications to +send messages to specific users was necessary. The obvious example is a +batch utility, running non-interactively, that wishes to communicate +errors or results to a user. However, the actual format, delivery +mechanism, and method of reading the message are clearly beyond the +scope of this volume of POSIX.1\(hy2017. +.P +The intent of this command is to provide a simple, portable interface +for sending messages non-interactively. It merely defines a +``front-end'' to the historical mail system. It is suggested that +implementations explicitly denote the sender and recipient in the body +of the delivered message. Further specification of formats for either +the message envelope or the message itself were deliberately not made, +as the industry is in the midst of changing from the current standards +to a more internationalized standard and it is probably incorrect, at +this time, to require either one. +.P +Implementations are encouraged to conform to the various delivery +mechanisms described in the CCITT X.400 standards or to the equivalent +Internet standards, described in Internet Request for Comment (RFC) +documents RFC\ 819, RFC\ 920, RFC\ 921, RFC\ 1123, and RFC\ 5322 (which +succeeded RFC\ 822). +.P +Many historical systems modified each body line that started with +.BR "From\0" +by prefixing the +.BR 'F' +with +.BR '>' . +It is unnecessary, but allowed, to do that when the string does not +follow a blank line because it cannot be confused with the next +header. +.P +The +.BR edit +and +.BR visual +commands merely edit the specified messages in a temporary file. They +do not modify the contents of those messages in the mailbox; such a +capability could be added as an extension, such as by using different +command names. +.P +The restriction on a subject line being +{LINE_MAX}\-10 +bytes is based on the historical format that consumes 10 bytes for +.BR "Subject:\0" +and the trailing +<newline>. +Many historical mailers that a message may encounter on other systems +are not able to handle lines that long, however. +.P +Like the utilities +.IR logger +and +.IR lp , +.IR mailx +admittedly is difficult to test. This was not deemed sufficient +justification to exclude this utility from this volume of POSIX.1\(hy2017. It is also arguable +that it is, in fact, testable, but that the tests themselves are not +portable. +.P +When +.IR mailx +is being used by an application that wishes to receive the results as +if none of the User Portability Utilities option features were +supported, the +.IR DEAD +environment variable must be set to +.BR /dev/null . +Otherwise, it may be subject to the file creations described in +.IR mailx +ASYNCHRONOUS EVENTS. Similarly, if the +.IR MAILRC +environment variable is not set to +.BR /dev/null , +historical versions of +.IR mailx +and +.IR Mail +read initialization commands from a file before processing begins. +Since the initialization that a user specifies could alter the contents +of messages an application is trying to send, such applications must +set +.IR MAILRC +to +.BR /dev/null . +.P +The description of +.IR LC_TIME +uses ``may affect'' because many historical implementations do not or +cannot manipulate the date and time strings in the incoming mail +headers. Some headers found in incoming mail do not have enough +information to determine the timezone in which the mail originated, +and, therefore, +.IR mailx +cannot convert the date and time strings into the internal form that +then is parsed by routines like +\fIstrftime\fR() +that can take +.IR LC_TIME +settings into account. Changing all these times to a user-specified +format is allowed, but not required. +.P +The paginator selected when +.IR PAGER +is null or unset is partially unspecified to allow the System V +historical practice of using +.IR pg +as the default. Bypassing the pagination function, such as by declaring +that +.IR cat +is the paginator, would not meet with the intended meaning of this +description. However, any ``portable user'' would have to set +.IR PAGER +explicitly to get his or her preferred paginator on all systems. The +paginator choice was made partially unspecified, unlike the +.IR VISUAL +editor choice (mandated to be +.IR vi ) +because most historical pagers follow a common theme of user input, +whereas editors differ dramatically. +.P +Options to specify addresses as +.BR cc +(carbon copy) or +.BR bcc +(blind carbon copy) were considered to be format details and were +omitted. +.P +A zero exit status implies that all messages were +.IR sent , +but it gives no assurances that any of them were actually +.IR delivered . +The reliability of the delivery mechanism is unspecified and is an +appropriate marketing distinction between systems. +.P +In order to conform to the Utility Syntax Guidelines, a solution was +required to the optional +.IR file +option-argument to +.BR \-f . +By making +.IR file +an operand, the guidelines are satisfied and users remain portable. +However, it does force implementations to support usage such as: +.sp +.RS 4 +.nf + +mailx -fin mymail.box +.fi +.P +.RE +.P +The +.BR no +.IR name +method of unsetting variables is not present in all historical systems, +but it is in System V and provides a logical set of commands +corresponding to the format of the display of options from the +.IR mailx +.IR set +command without arguments. +.P +The +.BR ask +and +.BR asksub +variables are the names selected by BSD and System V, respectively, for +the same feature. They are synonyms in this volume of POSIX.1\(hy2017. +.P +The +.IR mailx +.IR echo +command was not documented in the BSD version and has been omitted here +because it is not obviously useful for interactive users. +.P +The default prompt on the System V +.IR mailx +is a +<question-mark>, +on BSD +.IR Mail +an +<ampersand>. +Since this volume of POSIX.1\(hy2017 chose the +.IR mailx +name, it kept the System V default, assuming that BSD users would not +have difficulty with this minor incompatibility (that they can +override). +.P +The meanings of +.BR r +and +.BR R +are reversed between System V +.IR mailx +and SunOS +.IR Mail . +Once again, since this volume of POSIX.1\(hy2017 chose the +.IR mailx +name, it kept the System V default, but allows the SunOS user to +achieve the desired results using +.BR flipr , +an internal variable in System V +.IR mailx , +although it has not been documented in the SVID. +.P +The +.BR indentprefix +variable, the +.BR retain +and +.BR unalias +commands, and the +.BR ~F +and +.BR ~M +command escapes were adopted from 4.3 BSD +.IR Mail . +.P +The +.BR version +command was not included because no sufficiently general specification +of the version information could be devised that would still be useful +to a portable user. This command name should be used by suppliers who +wish to provide version information about the +.IR mailx +command. +.P +The ``implementation-specific (unspecified) system start-up file'' +historically has been named +.BR /etc/mailx.rc , +but this specific name and location are not required. +.P +The intent of the wording for the +.BR next +command is that if any command has already displayed the current +message it should display a following message, but, otherwise, it +should display the current message. Consider the command sequence: +.sp +.RS 4 +.nf + +next 3 +delete 3 +next +.fi +.P +.RE +.P +where the +.BR autoprint +option was not set. The normative text specifies that the second +.BR next +command should display a message following the third message, because +even though the current message has not been displayed since it was set +by the +.BR delete +command, it has been displayed since the current message was anything +other than message number 3. This does not always match historical +practice in some implementations, where the command file address +followed by +.BR next +(or the default command) would skip the message for which the user had +searched. +.SH "FUTURE DIRECTIONS" +None. +.SH "SEE ALSO" +.IR "Chapter 2" ", " "Shell Command Language", +.IR "\fIed\fR\^", +.IR "\fIls\fR\^", +.IR "\fImore\fR\^", +.IR "\fIvi\fR\^" +.P +The Base Definitions volume of POSIX.1\(hy2017, +.IR "Chapter 8" ", " "Environment Variables", +.IR "Section 12.2" ", " "Utility Syntax Guidelines" +.\" +.SH COPYRIGHT +Portions of this text are reprinted and reproduced in electronic form +from IEEE Std 1003.1-2017, Standard for Information Technology +-- Portable Operating System Interface (POSIX), The Open Group Base +Specifications Issue 7, 2018 Edition, +Copyright (C) 2018 by the Institute of +Electrical and Electronics Engineers, Inc and The Open Group. +In the event of any discrepancy between this version and the original IEEE and +The Open Group Standard, the original IEEE and The Open Group Standard +is the referee document. The original Standard can be obtained online at +http://www.opengroup.org/unix/online.html . +.PP +Any typographical or formatting errors that appear +in this page are most likely +to have been introduced during the conversion of the source files to +man page format. To report such errors, see +https://www.kernel.org/doc/man-pages/reporting_bugs.html . |