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PSIGNAL(3)	      DragonFly Library Functions Manual	    PSIGNAL(3)

NAME

psignal, strsignal, sys_siglist, sys_signame, sys_nsig -- system signal messages

LIBRARY

Standard C Library (libc, -lc)

SYNOPSIS

#include <signal.h> void psignal(unsigned sig, const char *s); extern const char * const sys_siglist[]; extern const char * const sys_signame[]; extern const int sys_nsig; #include <string.h> char * strsignal(int sig);

DESCRIPTION

The psignal() and strsignal() functions locate the descriptive message string for a signal number. The strsignal() function accepts a signal number argument sig and returns a pointer to the corresponding message string. The psignal() function accepts a signal number argument sig and writes it to the standard error. If the argument s is non-NULL and does not point to the null character, s is written to the standard error file descriptor prior to the message string, immediately followed by a colon and a space. If the signal number is not recognized (sigaction(2)), the string ``Unknown signal'' is produced. The message strings can be accessed directly through the external array sys_siglist, indexed by recognized signal numbers. The external array sys_signame is used similarly and contains short, lower-case abbrevia- tions for signals which are useful for recognizing signal names in user input. The external variable sys_nsig contains a count of the strings in sys_siglist and sys_signame. Note that the defined variable NSIG will typically be the same as sys_nsig, but might be different due to newer or older kernels and newer or older libc libraries. For maximum portability you must use sys_nsig to limit-check the above arrays. Additionally, you should check for NULL array entries and generate a generic signal name in those cases.

SEE ALSO

sigaction(2), perror(3), strerror(3)

HISTORY

The psignal() function appeared in 4.2BSD. DragonFly 3.7 February 27, 1995 DragonFly 3.7