#pragma force_top_level
#pragma include_only_once

/* signal.h: ANSI 'C' (X3J11 Oct 88) library header, section 4.7 */
/* Copyright (C) Codemist Ltd., 1988-1993.                       */
/* Copyright (C) Advanced Risc Machines Ltd., 1991-1993.         */
/* version 0.03 */

/*
 * signal.h declares a type and two functions and defines several macros, for
 * handling various signals (conditions that may be reported during program
 * execution).
 */

#ifndef __signal_h
#define __signal_h

#ifdef __cplusplus
extern "C" {
#endif

typedef int sig_atomic_t;
   /* type which is the integral type of an object that can be modified as */
   /* an atomic entity, even in the presence of asynchronous interrupts. */

extern void __SIG_DFL(int);
extern void __SIG_ERR(int);
extern void __SIG_IGN(int);
   /*
    * Each of the following macros expand to a constant expression with a
    * distinct value and has the same type as the second argument to, and the
    * return value of the signal function, and whose value compares unequal to
    * the address of any declarable function.
    */
#define SIG_DFL &__SIG_DFL
#define SIG_ERR &__SIG_ERR
#define SIG_IGN &__SIG_IGN

   /*
    * Each of the following macros expand to a positive integral constant
    * expression that is the signal number corresponding the the specified
    * condition.
    */
#define SIGABRT 1   /* abort                         */
#define SIGFPE  2   /* arithmetic exception          */
#define SIGILL  3   /* illegal instruction           */
#define SIGINT  4   /* attention request from user   */
#define SIGSEGV 5   /* bad memory access             */
#define SIGTERM 6   /* termination request           */
#define SIGSTAK 7   /* stack overflow                */
   /* (these following macros are not part of the ANSI standard,
    * but private to this implementation
    */
/* Signal numbers 8 and 9 are available for the user */
#define SIGUSR1 8
#define SIGUSR2 9
#define SIGOSERROR 10

extern void (*signal (int /*sig*/, void (* /*func*/ )(int)))(int);
   /*
    * Chooses one of three ways in which receipt of the signal number sig is to
    * be subsequently handled. If the value of func is SIG_DFL, default
    * handling for that signal will occur. If the value of func is SIG_IGN, the
    * signal will be ignored. Otherwise func shall point to a function to be
    * called when that signal occurs.
    * When a signal occurs, if func points to a function, first the equivalent
    * of signal(sig, SIG_DFL); is executed. (If the value of sig is SIGILL,
    * whether the reset to SIG_DFL occurs is implementation-defined (under
    * RISCOS/Arthur/Brazil the reset does occur)). Next the equivalent of
    * (*func)(sig); is executed. The function may terminate by calling the
    * abort, exit or longjmp function. If func executes a return statement and
    * the value of sig was SIGFPE or any other implementation-defined value
    * corresponding to a computational exception, the behaviour is undefined.
    * Otherwise, the program will resume execution at the point it was
    * interrupted.
    * If the signal occurs other than as a result of calling the abort or raise
    * function, the behaviour is undefined if the signal handler calls any
    * function in the standard library other than the signal function itself
    * or refers to any object with static storage duration other than by
    * assigning a value to a volatile static variable of type sig_atomic_t.
    * At program startup, the equivalent of signal(sig, SIG_IGN); may be
    * executed for some signals selected in an implementation-defined manner
    * (under RISCOS/Arthur/Brazil this does not occur); the equivalent of
    * signal(sig, SIG_DFL); is executed for all other signals defined by the
    * implementation.
    * Returns: If the request can be honoured, the signal function returns the
    *          value of func for most recent call to signal for the specified
    *          signal sig. Otherwise, a value of SIG_ERR is returned and the
    *          integer expression errno is set to indicate the error.
    */

extern int raise(int /*sig*/);
   /* sends the signal sig to the executing program. */
   /* Returns: zero if successful, non-zero if unsuccessful. */

#ifdef __cplusplus
}
#endif

#endif

/* end of signal.h */