HPUX signal[3f]

 SIGNAL(3F)                                                       SIGNAL(3F)

                  +U77 FORTRAN compile-line option required



 NAME
      signal - change the action for a signal

 SYNOPSIS
      INTEGER*4 function signal(signum, proc, flag)
      INTEGER*4 signum, flag
      external proc

 DESCRIPTION
      When a process incurs a signal (see signal(5)) the default action is
      usually to clean up and abort.  The user may choose to write an
      alternative signal handling routine.  A call to signal is the way this
      alternate action is specified to the system.

      Signum is the signal number (see signal(5)).  If flag is negative,
      then proc must be the name of the user signal handling routine.  If
      flag is zero or positive, then proc is ignored and the value of flag
      is passed to the system as the signal action definition.  In
      particular, this is how previously saved signal actions can be
      restored.  Two possible values for flag have specific meanings: 0
      means "use the default action" (See NOTES below), 1 means "ignore this
      signal".

      A positive returned value is the previous action definition.  A value
      greater than 1 is the address of a routine that was to have been
      called on occurrence of the given signal.  The returned value can be
      used in subsequent calls to signal in order to restore a previous
      action definition.  A negative returned value is the negation of a
      system error code.  (See perror(3F))

 FILES
      /usr/lib/libU77.a

 SEE ALSO
      signal(2), signal(5), kill(3F), kill(1)

 NOTES
      f77 arranges to trap certain signals when a process is started.  The
      only way to restore the default f77 action is to save the returned
      value from the first call to signal.

      If the user signal handler is called, it will be passed the signal
      number as an INTEGER*4 argument.











 Hewlett-Packard Company            - 1 -       HP-UX Release 9.0: June 1992