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diff --git a/man-pages-posix-2017/man3p/closelog.3p b/man-pages-posix-2017/man3p/closelog.3p new file mode 100644 index 0000000..2b5a2af --- /dev/null +++ b/man-pages-posix-2017/man3p/closelog.3p @@ -0,0 +1,293 @@ +'\" et +.TH CLOSELOG "3P" 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 +closelog, +openlog, +setlogmask, +syslog +\(em control system log +.SH SYNOPSIS +.LP +.nf +#include <syslog.h> +.P +void closelog(void); +void openlog(const char *\fIident\fP, int \fIlogopt\fP, int \fIfacility\fP); +int setlogmask(int \fImaskpri\fP); +void syslog(int \fIpriority\fP, const char *\fImessage\fP, ... /* \fIarguments\fP */); +.fi +.SH DESCRIPTION +The +\fIsyslog\fR() +function shall send a message to an implementation-defined logging +facility, which may log it in an implementation-defined system log, +write it to the system console, forward it to a list of users, or +forward it to the logging facility on another host over the network. +The logged message shall include a message header and a message body. +The message header contains at least a timestamp and a tag string. +.P +The message body is generated from the +.IR message +and following arguments in the same manner as if these were arguments +to +\fIprintf\fR(), +except that the additional conversion specification +.BR %m +shall be recognized; it shall convert no arguments, shall cause the +output of the error message string associated with the value of +.IR errno +on entry to +\fIsyslog\fR(), +and may be mixed with argument specifications of the \fR"%\fIn\fR$"\fR +form. If a complete conversion specification with the +.BR m +conversion specifier character is not just +.BR %m , +the behavior is undefined. A trailing +<newline> +may be added if needed. +.P +Values of the +.IR priority +argument are formed by OR'ing together a severity-level value and an +optional facility value. If no facility value is specified, the current +default facility value is used. +.P +Possible values of severity level include: +.IP LOG_EMERG 12 +A panic condition. +.IP LOG_ALERT 12 +A condition that should be corrected immediately, such as a corrupted +system database. +.IP LOG_CRIT 12 +Critical conditions, such as hard device errors. +.IP LOG_ERR 12 +Errors. +.IP LOG_WARNING 12 +.br +Warning messages. +.IP LOG_NOTICE 12 +Conditions that are not error conditions, but that may require special +handling. +.IP LOG_INFO 12 +Informational messages. +.IP LOG_DEBUG 12 +Messages that contain information normally of use only when debugging a +program. +.P +The facility indicates the application or system component generating +the message. Possible facility values include: +.IP LOG_USER 12 +Messages generated by arbitrary processes. This is the default facility +identifier if none is specified. +.IP LOG_LOCAL0 12 +Reserved for local use. +.IP LOG_LOCAL1 12 +Reserved for local use. +.IP LOG_LOCAL2 12 +Reserved for local use. +.IP LOG_LOCAL3 12 +Reserved for local use. +.IP LOG_LOCAL4 12 +Reserved for local use. +.IP LOG_LOCAL5 12 +Reserved for local use. +.IP LOG_LOCAL6 12 +Reserved for local use. +.IP LOG_LOCAL7 12 +Reserved for local use. +.P +The +\fIopenlog\fR() +function shall set process attributes that affect subsequent calls to +\fIsyslog\fR(). +The +.IR ident +argument is a string that is prepended to every message. The +.IR logopt +argument indicates logging options. Values for +.IR logopt +are constructed by a bitwise-inclusive OR of zero or more of the +following: +.IP LOG_PID 12 +Log the process ID with each message. This is useful for identifying +specific processes. +.IP LOG_CONS 12 +Write messages to the system console if they cannot be sent to the +logging facility. The +\fIsyslog\fR() +function ensures that the process does not acquire the console as a +controlling terminal in the process of writing the message. +.IP LOG_NDELAY 12 +Open the connection to the logging facility immediately. Normally the +open is delayed until the first message is logged. This is useful for +programs that need to manage the order in which file descriptors are +allocated. +.IP LOG_ODELAY 12 +Delay open until +\fIsyslog\fR() +is called. +.IP LOG_NOWAIT 12 +Do not wait for child processes that may have been created during the +course of logging the message. This option should be used by processes +that enable notification of child termination using SIGCHLD, since +\fIsyslog\fR() +may otherwise block waiting for a child whose exit status has already +been collected. +.P +The +.IR facility +argument encodes a default facility to be assigned to all messages that +do not have an explicit facility already encoded. The initial default +facility is LOG_USER. +.P +The +\fIopenlog\fR() +and +\fIsyslog\fR() +functions may allocate a file descriptor. It is not necessary to call +\fIopenlog\fR() +prior to calling +\fIsyslog\fR(). +.P +The +\fIcloselog\fR() +function shall close any open file descriptors allocated by previous +calls to +\fIopenlog\fR() +or +\fIsyslog\fR(). +.P +The +\fIsetlogmask\fR() +function shall set the log priority mask for the current process to +.IR maskpri +and return the previous mask. If the +.IR maskpri +argument is 0, the current log mask is not modified. Calls by the +current process to +\fIsyslog\fR() +with a priority not set in +.IR maskpri +shall be rejected. The default log mask allows all priorities to be +logged. A call to +\fIopenlog\fR() +is not required prior to calling +\fIsetlogmask\fR(). +.P +Symbolic constants for use as values of the +.IR logopt , +.IR facility , +.IR priority , +and +.IR maskpri +arguments are defined in the +.IR <syslog.h> +header. +.SH "RETURN VALUE" +The +\fIsetlogmask\fR() +function shall return the previous log priority mask. The +\fIcloselog\fR(), +\fIopenlog\fR(), +and +\fIsyslog\fR() +functions shall not return a value. +.SH ERRORS +No errors are defined. +.LP +.IR "The following sections are informative." +.SH EXAMPLES +.SS "Using openlog(\|)" +.P +The following example causes subsequent calls to +\fIsyslog\fR() +to log the process ID with each message, and to write messages to the +system console if they cannot be sent to the logging facility. +.sp +.RS 4 +.nf + +#include <syslog.h> +.P +char *ident = "Process demo"; +int logopt = LOG_PID | LOG_CONS; +int facility = LOG_USER; +\&... +openlog(ident, logopt, facility); +.fi +.P +.RE +.SS "Using setlogmask(\|)" +.P +The following example causes subsequent calls to +\fIsyslog\fR() +to accept error messages, and to reject all other messages. +.sp +.RS 4 +.nf + +#include <syslog.h> +.P +int result; +int mask = LOG_MASK (LOG_ERR); +\&... +result = setlogmask(mask); +.fi +.P +.RE +.SS "Using syslog" +.P +The following example sends the message +.BR \(dqThis is a message\(dq +to the default logging facility, marking the message as an error +message generated by random processes. +.sp +.RS 4 +.nf + +#include <syslog.h> +.P +char *message = "This is a message"; +int priority = LOG_ERR | LOG_USER; +\&... +syslog(priority, message); +.fi +.P +.RE +.SH "APPLICATION USAGE" +None. +.SH RATIONALE +None. +.SH "FUTURE DIRECTIONS" +None. +.SH "SEE ALSO" +.IR "\fIfprintf\fR\^(\|)" +.P +The Base Definitions volume of POSIX.1\(hy2017, +.IR "\fB<syslog.h>\fP" +.\" +.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 . |