gsignal, ssignal — software signal facility
#include <signal.h> typedef void (*sighandler_t)(int);
int
gsignal( |
signum) ; |
sighandler_t ssignal( |
int | signum, |
sighandler_t | action) ; |
Don't use these functions under Linux. Due to a historical mistake, under Linux these functions are aliases for raise(3) and signal(2), respectively.
Elsewhere, on System V-like systems, these functions
implement software signalling, entirely independent of the
classical signal and kill functions. The function
ssignal
() defines the action to
take when the software signal with number signum
is raised using the
function gsignal
(), and returns
the previous such action or SIG_DFL. The function
gsignal
() does the following:
if no action (or the action SIG_DFL) was specified for
signum
, then it does
nothing and returns 0. If the action SIG_IGN was specified
for signum
, then it
does nothing and returns 1. Otherwise, it resets the action
to SIG_DFL and calls the action function with parameter
signum
, and returns
the value returned by that function. The range of possible
values signum
varies
(often 1-15 or 1-17).
These functions are available under AIX, DG/UX, HP-UX,
SCO, Solaris, Tru64. They are called obsolete under most of
these systems, and are broken under Linux libc and glibc.
Some systems also have gsignal_r
() and ssignal_r
().
|