GSIGNAL(3)                          Linux Programmer's Manual                          GSIGNAL(3)



NAME
       gsignal, ssignal - software signal facility

SYNOPSIS
       #include <signal.h>

       typedef void (*sighandler_t)(int);

       int gsignal(int signum);

       sighandler_t ssignal(int signum, sighandler_t action);

   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

       gsignal(), ssignal(): _SVID_SOURCE

DESCRIPTION
       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  signaling,
       entirely independent of the classical signal(2) and kill(2) functions.  The function ssig‐
       nal() 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 func‐
       tion 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 argument signum, and returns the value returned by that
       function.  The range of possible values signum varies (often 1-15 or 1-17).

CONFORMING TO
       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().

SEE ALSO
       kill(2), signal(2), raise(3)

COLOPHON
       This page is part of release 3.74 of the Linux man-pages project.  A  description  of  the
       project,  information  about  reporting  bugs, and the latest version of this page, can be
       found at http://www.kernel.org/doc/man-pages/.



                                            2007-07-26                                 GSIGNAL(3)