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diff --git a/man-pages-posix-2017/man1p/id.1p b/man-pages-posix-2017/man1p/id.1p new file mode 100644 index 0000000..8a16389 --- /dev/null +++ b/man-pages-posix-2017/man1p/id.1p @@ -0,0 +1,353 @@ +'\" et +.TH ID "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 +id +\(em return user identity +.SH SYNOPSIS +.LP +.nf +id \fB[\fIuser\fB]\fR +.P +id -G \fB[\fR-n\fB] [\fIuser\fB]\fR +.P +id -g \fB[\fR-nr\fB] [\fIuser\fB]\fR +.P +id -u \fB[\fR-nr\fB] [\fIuser\fB]\fR +.fi +.SH DESCRIPTION +If no +.IR user +operand is provided, the +.IR id +utility shall write the user and group IDs and the corresponding user +and group names of the invoking process to standard output. If the +effective and real IDs do not match, both shall be written. If +multiple groups are supported by the underlying system (see the +description of +{NGROUPS_MAX} +in the System Interfaces volume of POSIX.1\(hy2017), the supplementary group affiliations of the invoking +process shall also be written. +.P +If a +.IR user +operand is provided and the process has appropriate privileges, the +user and group IDs of the selected user shall be written. In this +case, effective IDs shall be assumed to be identical to real IDs. If +the selected user has more than one allowable group membership listed +in the group database, these shall be written in the same manner as the +supplementary groups described in the preceding paragraph. +.SH OPTIONS +The +.IR id +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: +.IP "\fB\-G\fP" 10 +Output all different group IDs (effective, real, and supplementary) +only, using the format +.BR \(dq%u\en\(dq . +If there is more than one distinct group affiliation, output each such +affiliation, using the format +.BR \(dq\ %u\(dq , +before the +<newline> +is output. +.IP "\fB\-g\fP" 10 +Output only the effective group ID, using the format +.BR \(dq%u\en\(dq . +.IP "\fB\-n\fP" 10 +Output the name in the format +.BR \(dq%s\(dq +instead of the numeric ID using the format +.BR \(dq%u\(dq . +.IP "\fB\-r\fP" 10 +Output the real ID instead of the effective ID. +.IP "\fB\-u\fP" 10 +Output only the effective user ID, using the format +.BR \(dq%u\en\(dq . +.SH OPERANDS +The following operand shall be supported: +.IP "\fIuser\fR" 10 +The login name for which information is to be written. +.SH STDIN +Not used. +.SH "INPUT FILES" +None. +.SH "ENVIRONMENT VARIABLES" +The following environment variables shall affect the execution of +.IR id : +.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). +.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 "\fINLSPATH\fP" 10 +Determine the location of message catalogs for the processing of +.IR LC_MESSAGES . +.SH "ASYNCHRONOUS EVENTS" +Default. +.SH STDOUT +The following formats shall be used when the +.IR LC_MESSAGES +locale category specifies the POSIX locale. In other locales, the +strings +.IR uid , +.IR gid , +.IR euid , +.IR egid , +and +.IR groups +may be replaced with more appropriate strings corresponding to the +locale. +.sp +.RS 4 +.nf + +"uid=%u(%s) gid=%u(%s)\en", <\fIreal user ID\fR>, <\fIuser-name\fR>, + <\fIreal group ID\fR>, <\fIgroup-name\fR> +.fi +.P +.RE +.P +If the effective and real user IDs do not match, the following shall be +inserted immediately before the +.BR '\en' +character in the previous format: +.sp +.RS 4 +.nf + +" euid=%u(%s)" +.fi +.P +.RE +.P +with the following arguments added at the end of the argument list: +.sp +.RS 4 +.nf + +<\fIeffective user ID\fR>, <\fIeffective user-name\fR> +.fi +.P +.RE +.P +If the effective and real group IDs do not match, the following shall +be inserted directly before the +.BR '\en' +character in the format string (and after any addition resulting from +the effective and real user IDs not matching): +.sp +.RS 4 +.nf + +" egid=%u(%s)" +.fi +.P +.RE +.P +with the following arguments added at the end of the argument list: +.sp +.RS 4 +.nf + +<\fIeffective group-ID\fR>, <\fIeffective group name\fR> +.fi +.P +.RE +.P +If the process has supplementary group affiliations or the selected +user is allowed to belong to multiple groups, the first shall be added +directly before the +<newline> +in the format string: +.sp +.RS 4 +.nf + +" groups=%u(%s)" +.fi +.P +.RE +.P +with the following arguments added at the end of the argument list: +.sp +.RS 4 +.nf + +<\fIsupplementary group ID\fR>, <\fIsupplementary group name\fR> +.fi +.P +.RE +.P +and the necessary number of the following added after that for any +remaining supplementary group IDs: +.sp +.RS 4 +.nf + +",%u(%s)" +.fi +.P +.RE +.P +and the necessary number of the following arguments added at the end of +the argument list: +.sp +.RS 4 +.nf + +<\fIsupplementary group ID\fR>, <\fIsupplementary group name\fR> +.fi +.P +.RE +.P +If any of the user ID, group ID, effective user ID, effective group ID, +or supplementary/multiple group IDs cannot be mapped by the system into +printable user or group names, the corresponding +.BR \(dq(%s)\(dq +and +.IR name +argument shall be omitted from the corresponding format string. +.P +When any of the options are specified, the output format shall be as +described in the OPTIONS section. +.SH STDERR +The standard error shall be used only for diagnostic messages. +.SH "OUTPUT FILES" +None. +.SH "EXTENDED DESCRIPTION" +None. +.SH "EXIT STATUS" +The following exit values shall be returned: +.IP "\00" 6 +Successful completion. +.IP >0 6 +An error occurred. +.SH "CONSEQUENCES OF ERRORS" +Default. +.LP +.IR "The following sections are informative." +.SH "APPLICATION USAGE" +Output produced by the +.BR \-G +option and by the default case could potentially produce very long +lines on systems that support large numbers of supplementary groups. +(On systems with user and group IDs that are 32-bit integers and with +group names with a maximum of 8 bytes per name, 93 supplementary groups +plus distinct effective and real group and user IDs could theoretically +overflow the 2\|048-byte +{LINE_MAX} +text file line limit on the default output case. It would take about +186 supplementary groups to overflow the 2\|048-byte barrier using +.IR id +.BR \-G ). +This is not expected to be a problem in practice, but in cases where it +is a concern, applications should consider using +.IR fold +.BR \-s +before post-processing the output of +.IR id . +.SH EXAMPLES +None. +.SH RATIONALE +The functionality provided by the 4 BSD +.IR groups +utility can be simulated using: +.sp +.RS 4 +.nf + +id -Gn [ user ] +.fi +.P +.RE +.P +The 4 BSD command +.IR groups +was considered, but it was not included because it did not provide the +functionality of the +.IR id +utility of the SVID. Also, it was thought that it would be easier to +modify +.IR id +to provide the additional functionality necessary to systems with +multiple groups than to invent another command. +.P +The options +.BR \-u , +.BR \-g , +.BR \-n , +and +.BR \-r +were added to ease the use of +.IR id +with shell commands substitution. Without these options it is +necessary to use some preprocessor such as +.IR sed +to select the desired piece of information. Since output such as that +produced by: +.sp +.RS 4 +.nf + +id -u -n +.fi +.P +.RE +.P +is frequently wanted, it seemed desirable to add the options. +.SH "FUTURE DIRECTIONS" +None. +.SH "SEE ALSO" +.IR "\fIfold\fR\^", +.IR "\fIlogname\fR\^", +.IR "\fIwho\fR\^" +.P +The Base Definitions volume of POSIX.1\(hy2017, +.IR "Chapter 8" ", " "Environment Variables", +.IR "Section 12.2" ", " "Utility Syntax Guidelines" +.P +The System Interfaces volume of POSIX.1\(hy2017, +.IR "\fIgetgid\fR\^(\|)", +.IR "\fIgetgroups\fR\^(\|)", +.IR "\fIgetuid\fR\^(\|)" +.\" +.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 . |