.\" Copyright 2002 walter harms (walter.harms@informatik.uni-oldenburg.de)
-.\" Distributed under GPL
+.\"
+.\" %%%LICENSE_START(GPL_NOVERSION_ONELINE)
+.\" Distributed under GPL
+.\" %%%LICENSE_END
+.\"
.\" adapted glibc info page
.\"
.\" This should run as 'Guru Meditation' (amiga joke :)
.\" The function is quite complex and deserves an example
.\"
.\" Polished, aeb, 2003-11-01
-.TH FMTMSG 3 2008-06-14 "" "Linux Programmer's Manual"
+.TH FMTMSG 3 2017-09-15 "" "Linux Programmer's Manual"
.SH NAME
fmtmsg \- print formatted error messages
.SH SYNOPSIS
.nf
.B #include <fmtmsg.h>
-.sp
+.PP
.BI "int fmtmsg(long " classification ", const char *" label ,
-.br
.BI " int " severity ", const char *" text ,
-.br
.BI " const char *" action ", const char *" tag );
.fi
.SH DESCRIPTION
-This function displays a message described by its parameters on the device(s)
+This function displays a message described by its arguments on the device(s)
specified in the
.I classification
-parameter.
+argument.
For messages written to
.IR stderr ,
the format depends on the
.B MSGVERB
environment variable.
-.LP
+.PP
The
.I label
-parameter identifies the source of the message.
+argument identifies the source of the message.
The string must consist
of two colon separated parts where the first part has not more
than 10 and the second part not more than 14 characters.
-.LP
+.PP
The
.I text
-parameter describes the condition of the error.
-.LP
+argument describes the condition of the error.
+.PP
The
.I action
-parameter describes possible steps to recover from the error.
+argument describes possible steps to recover from the error.
If it is printed, it is prefixed by "TO FIX: ".
-.LP
+.PP
The
.I tag
-parameter is a reference to the online documentation where more
+argument is a reference to the online documentation where more
information can be found.
It should contain the
.I label
value and a unique identification number.
-.SS "Dummy parameters"
-Each of the parameters can have a dummy value.
+.SS Dummy arguments
+Each of the arguments can have a dummy value.
The dummy classification value
.B MM_NULLMC
(0L) does not specify any output, so nothing is printed.
.BR MM_NULLACT ,
.B MM_NULLTAG
are synonyms for
-.IR "((char *) 0)" ,
+.IR "((char\ *)\ 0)" ,
the empty string, and
.B MM_NULLSEV
is a synonym for
.BR NO_SEV .
-.SS "The classification parameter"
+.SS The classification argument
The
.I classification
-parameter is the sum of values describing 4 types of information.
-.br
-.sp
+argument is the sum of values describing 4 types of information.
+.PP
The first value defines the output channel.
.TP 12n
.B MM_PRINT
It is a recoverable error.
.TP
.B MM_NRECOV
-It is a non-recoverable error.
-.SS "The severity parameter"
+It is a nonrecoverable error.
+.SS The severity argument
The
.I severity
-parameter can take one of the following values:
+argument can take one of the following values:
.TP 12n
.B MM_NOSEV
No severity is printed.
or the environment variable
.B SEV_LEVEL
you can add more levels and strings to print.
-.SH "RETURN VALUE"
+.SH RETURN VALUE
The function can return 4 values:
.TP 12n
.B MM_OK
If the user puts
.B SEV_LEVEL
with a format like
-.sp
+.PP
.RS
SEV_LEVEL=[description[:description[:...]]]
.RE
-.sp
+.PP
in the environment of the process before the first call to
.BR fmtmsg (),
where each description is of the form
-.sp
+.PP
.RS
severity-keyword,level,printstring
.RE
-.sp
+.PP
then
.BR fmtmsg ()
will also accept the indicated values for the level (in addition to
-the standard levels 0-4), and use the indicated printstring when
+the standard levels 0\(en4), and use the indicated printstring when
such a level occurs.
-.LP
+.PP
The severity-keyword part is not used by
.BR fmtmsg ()
but it has to be present.
The level part is a string representation of a number.
The numeric value must be a number greater than 4.
-This value must be used in the severity parameter of
+This value must be used in the severity argument of
.BR fmtmsg ()
to select this class.
It is not possible to overwrite
.SH VERSIONS
.BR fmtmsg ()
is provided in glibc since version 2.1.
-.SH "CONFORMING TO"
+.SH ATTRIBUTES
+For an explanation of the terms used in this section, see
+.BR attributes (7).
+.TS
+allbox;
+lb lb lbw23
+l l l.
+Interface Attribute Value
+T{
+.BR fmtmsg ()
+T} Thread safety T{
+glibc >= 2.16: MT-Safe
+.br
+glibc < 2.16: MT-Unsafe
+T}
+.TE
+.PP
+Before glibc 2.16, the
+.BR fmtmsg ()
+function uses a static variable that is not protected,
+so it is not thread-safe.
+.PP
+Since glibc 2.16,
+.\" Modified in commit 7724defcf8873116fe4efab256596861eef21a94
+the
+.BR fmtmsg ()
+function uses a lock to protect the static variable, so it is thread-safe.
+.SH CONFORMING TO
The functions
.BR fmtmsg ()
and
and
.B SEV_LEVEL
come from System V.
+.PP
The function
.BR fmtmsg ()
and the environment variable
.B MSGVERB
-are described in POSIX.1-2001.
+are described in POSIX.1-2001 and POSIX.1-2008.
.SH NOTES
-System V and Unixware man pages tell us that these functions
+System V and UnixWare man pages tell us that these functions
have been replaced by "pfmt() and addsev()" or by "pfmt(),
vpfmt(), lfmt(), and vlfmt()", and will be removed later.
-.SH EXAMPLE
-.nf
+.SH EXAMPLES
+.EX
#include <stdio.h>
#include <stdlib.h>
#include <fmtmsg.h>
}
exit(EXIT_SUCCESS);
}
-.fi
+.EE
.PP
The output should be:
-.nf
-
- util\-linux:mount: ERROR: unknown mount option
- TO FIX: See mount(8). util\-linux:mount:017
-
-.fi
+.PP
+.in +4n
+.EX
+util\-linux:mount: ERROR: unknown mount option
+TO FIX: See mount(8). util\-linux:mount:017
+.EE
+.in
+.PP
and after
-.nf
-
- MSGVERB=text:action; export MSGVERB
-
-.fi
+.PP
+.in +4n
+.EX
+MSGVERB=text:action; export MSGVERB
+.EE
+.in
+.PP
the output becomes:
-.nf
-
- unknown mount option
- TO FIX: See mount(8).
-.fi
-.SH "SEE ALSO"
+.PP
+.in +4n
+.EX
+unknown mount option
+TO FIX: See mount(8).
+.EE
+.in
+.PP
+.SH SEE ALSO
.BR addseverity (3),
.BR perror (3)
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