FMTMSG(3) Library Functions Manual FMTMSG(3)
fmtmsg -- format and display a message
Standard C Library (libc, -lc)
fmtmsg(long classification, const char *label, int severity, const char
*text, const char *action, const char *tag);
The fmtmsg() function can be used to display messages in the specified
format. Messages may be written either to standard error, to the
console, or both.
A formatted message consists of up to five components specified in label,
severity, text, action and tag. Further information such as the origin
of the message, the recoverability from the condition causing the message
and where to display the message is specified in classification.
The classification argument consists of a major classification and
several sub-classifications. It has no effect on the content of the
message displayed. With the exception of the display sub-classification,
only a single identifier may be specified for each (sub-)classification.
The following classifications are available:
The source of the condition. Available identifiers are: MM_HARD
(hardware), MM_SOFT (software), and MM_FIRM (firmware).
Message source sub-classifications
The type of software detecting the condition. Available identifiers
are: MM_APPL (application), MM_UTIL (utility), and MM_OPSYS
The displays the formatted messages is to be written to. Available
identifiers are: MM_PRINT (standard error stream) and MM_CONSOLE
The capability of the calling software to recover from the
condition. Available identifiers are: MM_RECOVER (recoverable) and
If no classification is to be supplied, MM_NULLMC must be specified.
The label argument identifies the source of the message. It consists of
two fields separated by a colon (:). The first field is up to 10
characters, the second is up to 14 characters.
If no label is to be supplied, MM_NULLLBL must be specified.
The seriousness of the condition causing the message. The following
severity levels are available:
MM_HALT The software has encountered a severe fault and is
MM_ERROR The software has encountered a fault.
MM_WARNING The software has encountered an unusual non-fault
MM_INFO The software informs about a non-error condition.
If no severity level is to be supplied, MM_NOSEV must be specified.
The description of the condition the software encountered. The character
string is not limited to a specific size.
If no text is to be supplied, MM_NOTXT must be specified.
The first step to be taken to recover from the condition the software
encountered; it will be preceded by the prefix ``TO FIX:''. The
character string is not limited to a specific size.
If no action is to be supplied, MM_NOACT must be specified.
The on-line documentation which provides further information about the
condition and the message, such as ``fmtmsg(3)''. The character string
is not limited to a specific size.
If no tag is to be supplied, MM_NOTAG must be specified.
Further effect on the formatting of the message as displayed on the
standard error stream (but not on the system console!) may be taken by
setting the MSGVERB environment variable, which selects the subset of
message components to be printed. It consists of a colon-separated list
of the optional keywords label, severity, text, action, and tag, which
correspond to the arguments to fmtmsg() with the same names. If MSGVERB
is either not set or malformed (containing empty or unknown keywords),
its content is ignored an all message components will be selected.
Note that displaying a message on the system console may fail due to
inappropriate privileges or a non-permissive file mode of the console
The fmtmsg() function returns one of the following values:
MM_OK The function succeeded.
MM_NOTOK The function failed completely.
MM_NOMSG The function was unable to generate a message on standard
error, but otherwise succeeded.
MM_NOCOM The function was unable to generate a message on the
console, but otherwise succeeded.
The fmtmsg() function conforms to X/Open System Interfaces and Headers
Issue 5 (``XSH5'').
NetBSD 6.1.5 April 11, 2011 NetBSD 6.1.5