Index for Section 3

Alphabetical listing for S

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ssignal(3)
NAME
  ssignal, ssignal_r, gsignal, gsignal_r - Set and raise a software signal

SYNOPSIS
  #include <signal.h>

  void *ssignal(
	  void (*function)(int))) (int );

  int gsignal(
	  int signal );

  The following functions are supported to maintain backward compatibility
  with previous versions of the operating system.

  void *ssignal_r(
	  void (*function) (int),
	  void (*sigs[]) (int))) (int );

  int gsignal_r(
	  int signal,
	  void (*sigs[]) (int) );

LIBRARY"
  Standard C Library (libc)

PARAMETERS
  signal
      Defines the signal.

  function
      Specifies the action associated with the signal.

  sigs
      Specifies the array of signal functions. This structure must have at
      least 21 entries, each of which must be initialized to 0 (zero) by the
      caller.

DESCRIPTION
  These functions are obsolete and are retained for compatibility with
  earlier versions of the operating system.

  The ssignal() and gsignal() functions implement a facility similar to that
  of the signal() function and the kill() system call. However, there is no
  connection between the two facilities. User programs can use the ssignal()
  and gsignal() functions to handle exception processing within an
  application.	signal() and related functions handle system-defined
  exceptions.

  The signals available are associated with integers in the range 1 to 15.
  Other values are reserved for use by the C library and should not be used.

  The ssignal() function associates the procedure specified by the function
  parameter with the signal specified by the signal parameter. The gsignal()
  function raises the signal, causing the procedure specified by the function
  parameter to be taken.

  The function parameter is either a pointer to a user-defined function, or
  either of the constants SIG_DFL (default action) or SIG_IGN (ignore
  signal). The ssignal() function returns the procedure that was previously
  established for that signal. If no procedure was established before or if
  the signal number is illegal, then ssignal() returns the value SIG_DFL.

  The gsignal() function raises the signal specified by the signal parameter
  by performing the following:

    ·  If the procedure for signal is SIG_DFL, the gsignal() function returns
       a value of 0 (zero) and takes no other action.

    ·  If the procedure for signal is SIG_IGN, the gsignal() function returns
       a value of 1 and takes no other action.

    ·  If the procedure for signal is a function, the function value is reset
       to SIG_DFL and the function is called with signal passed as its
       parameter. The gsignal() function returns the value returned by the
       calling function with a single integer argument, which is the value of
       signal.

    ·  If the procedure for signal is illegal or if no procedure is specified
       for that signal, gsignal() returns a value of 0 (zero) and takes no
       other action.

NOTES
  The ssignal_r() and gsignal_r() functions are the reentrant versions of the
  ssignal() and gsignal() functions. They are supported in order to maintain
  backward compatibility with previous versions of the operating system. Upon
  successful completion, the ssignal_r() and gsignal_r() functions place
  pointers in or retrieve pointers from the signal structure in sigs.

RETURN VALUES
  The ssignal() and ssignal_r() functions return the value of the previously
  installed function if there was one, or SIG_DFL if there was not a
  previously installed function. If the value of signal was illegal the
  ssignal() and ssignal_r() functions return SIG_DFL.

  The gsignal() and gsignal_r() functions return a value of 0 (zero) if the
  procedure for signal is illegal, or if SIG_DFL is the action for signal.
  The gsignal() and gsignal_r() functions return a value of 1 if the
  procedure for signal is SIG_IGN. If none of these are true, then the
  gsignal() and gsignal_r() functions return the value returned by the
  calling function.

SEE ALSO
  Functions: kill(2) signal(2).

Index for Section 3

Alphabetical listing for S

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