setlogmask(3) Library Functions Manual setlogmask(3)
NAME
setlogmask - set log priority mask
LIBRARY
Standard C library (libc, -lc)
SYNOPSIS
#include <syslog.h>
int setlogmask(int mask);
DESCRIPTION
A process has a log priority mask that determines which calls to sys-
log(3) may be logged. All other calls will be ignored. Logging is en-
abled for the priorities that have the corresponding bit set in mask.
The initial mask is such that logging is enabled for all priorities.
The setlogmask() function sets this logmask for the calling process,
and returns the previous mask. If the mask argument is 0, the current
logmask is not modified.
The eight priorities are LOG_EMERG, LOG_ALERT, LOG_CRIT, LOG_ERR,
LOG_WARNING, LOG_NOTICE, LOG_INFO, and LOG_DEBUG. The bit correspond-
ing to a priority p is LOG_MASK(p). Some systems also provide a macro
LOG_UPTO(p) for the mask of all priorities in the above list up to and
including p.
RETURN VALUE
This function returns the previous log priority mask.
ERRORS
None.
ATTRIBUTES
For an explanation of the terms used in this section, see attrib-
utes(7).
┌────────────────────────────┬───────────────┬────────────────────────┐
│ Interface │ Attribute │ Value │
├────────────────────────────┼───────────────┼────────────────────────┤
│ setlogmask() │ Thread safety │ MT-Unsafe race:LogMask │
└────────────────────────────┴───────────────┴────────────────────────┘
STANDARDS
POSIX.1-2008.
HISTORY
POSIX.1-2001.
LOG_UPTO() will be included in the next release of the POSIX specifica-
tion (Issue 8).
SEE ALSO
closelog(3), openlog(3), syslog(3)
Linux man-pages 6.7 2023-11-01 setlogmask(3)
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