gsignal(3)                                            Library Functions Manual                                           gsignal(3)

       gsignal, ssignal - software signal facility

       Standard C library (libc, -lc)

       #include <signal.h>

       typedef void (*sighandler_t)(int);

       [[deprecated]] int gsignal(int signum);

       [[deprecated]] sighandler_t ssignal(int signum, sighandler_t action);

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

       gsignal(), ssignal():
           Since glibc 2.19:
           glibc 2.19 and earlier:

       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 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 argument signum, and returns the value returned by that function.  The range of possible val‐
       ues signum varies (often 1–15 or 1–17).

       For an explanation of the terms used in this section, see attributes(7).

       │Interface                                                                                │ Attribute     │ Value           │
       │gsignal()                                                                                │ Thread safety │ MT-Safe         │
       │ssignal()                                                                                │ Thread safety │ MT-Safe sigintr │

       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 glibc.  Some systems also have gsignal_r() and ssignal_r().

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

Linux man-pages 6.03                                         2023-02-05                                                  gsignal(3)