gsignal(3) — Linux manual page


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

NAME         top

       gsignal, ssignal - software signal facility

SYNOPSIS         top

       #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():
           Since glibc 2.19:
           Glibc 2.19 and earlier:

DESCRIPTION         top

       Don't use these functions under Linux.  Due to a historical mistake,
       under Linux these functions are aliases for raise(3) and signal(2),

       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
       values signum varies (often 1–15 or 1–17).

ATTRIBUTES         top

       For an explanation of the terms used in this section, see

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

CONFORMING TO         top

       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

SEE ALSO         top

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

COLOPHON         top

       This page is part of release 5.08 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

                                 2020-04-11                       GSIGNAL(3)