raise.c

标准c库代码,可以应用于各个系统提供了大量的基本函数

/* Embedded systems may want the simulated signals if no other form exists,
   but UNIX versions will want to use the host facilities.
   Define SIMULATED_SIGNALS when you want to use the simulated versions.
*/

/*
FUNCTION
<<raise>>---send a signal

INDEX
	raise
INDEX
	_raise_r

ANSI_SYNOPSIS
	#include <signal.h>
	int raise(int <[sig]>);

	int _raise_r(void *<[reent]>, int <[sig]>);

TRAD_SYNOPSIS
	#include <signal.h>
	int raise(<[sig]>)
	int <[sig]>;

	int _raise_r(<[reent]>, <[sig]>)
	char *<[reent]>;
	int <[sig]>;

DESCRIPTION
Send the signal <[sig]> (one of the macros from `<<sys/signal.h>>').
This interrupts your program's normal flow of execution, and allows a signal
handler (if you've defined one, using <<signal>>) to take control.

The alternate function <<_raise_r>> is a reentrant version.  The extra
argument <[reent]> is a pointer to a reentrancy structure.

RETURNS
The result is <<0>> if <[sig]> was successfully raised, <<1>>
otherwise.  However, the return value (since it depends on the normal
flow of execution) may not be visible, unless the signal handler for
<[sig]> terminates with a <<return>> or unless <<SIG_IGN>> is in
effect for this signal.

PORTABILITY
ANSI C requires <<raise>>, but allows the full set of signal numbers
to vary from one implementation to another.

Required OS subroutines: <<getpid>>, <<kill>>.
*/

#ifdef SIMULATED_SIGNALS

int _dummy_raise;

#else

#include <reent.h>
#include <signal.h>

#ifndef _REENT_ONLY

int
_DEFUN (raise, (sig),
	int sig)
{
  return _raise_r (_REENT, sig);
}

#endif

int
_DEFUN (_raise_r, (reent, sig),
	struct _reent *reent _AND
	int sig)
{
  return _kill_r (reent, _getpid_r (reent), sig);
}

#endif /* ! SIMULATED_SIGNALS */