Return to signal.3c CVS log

Up to [Power 6/32 Unix Tahoe 4.2BSD] / cci / usr / src / man / man3

Annotation of cci/usr/src/man/man3/signal.3c, revision 1.1

1.1     ! root        1: .TH SIGNAL 3C "15 June 1983"
        !             2: .UC 4
        !             3: .ie t .ds d \(dg
        !             4: .el .ds d \z'|+'
        !             5: .ie t .ds b \(bu
        !             6: .el .ds b @
        !             7: .SH NAME
        !             8: signal \- simplified software signal facilities
        !             9: .SH SYNOPSIS
        !            10: .nf
        !            11: .B #include <signal.h>
        !            12: .PP
        !            13: .B (*signal(sig, func))()
        !            14: .B void (*func)();
        !            15: .fi
        !            16: .SH DESCRIPTION
        !            17: .I Signal
        !            18: is a simplified interface to the more general
        !            19: .IR sigvec (2)
        !            20: facility.
        !            21: .PP
        !            22: A signal
        !            23: is generated by some abnormal event,
        !            24: initiated by a user at a terminal (quit, interrupt, stop),
        !            25: by a program error (bus error, etc.),
        !            26: by request of another program (kill),
        !            27: or when a process is stopped because it wishes to access
        !            28: its control terminal while in the background (see
        !            29: .IR tty (4)).
        !            30: Signals are optionally generated
        !            31: when a process resumes after being stopped,
        !            32: when the status of child processes changes,
        !            33: or when input is ready at the control terminal.
        !            34: Most signals cause termination of the receiving process if no action
        !            35: is taken; some signals instead cause the process receiving them
        !            36: to be stopped, or are simply discarded if the process has not
        !            37: requested otherwise.
        !            38: Except for the SIGKILL and SIGSTOP
        !            39: signals, the
        !            40: .I signal
        !            41: call allows signals either to be ignored
        !            42: or to cause an interrupt to a specified location.
        !            43: The following is a list of all signals with
        !            44: names as in the include file
        !            45: .RI < signal.h >:
        !            46: .LP
        !            47: .nf
        !            48: .ta \w'SIGVTALRM 'u +\w'15*  'u
        !            49: SIGHUP 1       hangup
        !            50: SIGINT 2       interrupt
        !            51: SIGQUIT        3*      quit
        !            52: SIGILL 4*      illegal instruction
        !            53: SIGTRAP        5*      trace trap
        !            54: SIGIOT 6*      IOT instruction
        !            55: SIGEMT 7*      EMT instruction
        !            56: SIGFPE 8*      floating point exception
        !            57: SIGKILL        9       kill (cannot be caught or ignored)
        !            58: SIGBUS 10*     bus error
        !            59: SIGSEGV        11*     segmentation violation
        !            60: SIGSYS 12*     bad argument to system call
        !            61: SIGPIPE        13      write on a pipe with no one to read it
        !            62: SIGALRM        14      alarm clock
        !            63: SIGTERM        15      software termination signal
        !            64: SIGURG 16\*b   urgent condition present on socket
        !            65: SIGSTOP        17\*d   stop (cannot be caught or ignored)
        !            66: SIGTSTP        18\*d   stop signal generated from keyboard
        !            67: SIGCONT        19\*b   continue after stop
        !            68: SIGCHLD        20\*b   child status has changed
        !            69: SIGTTIN        21\*d   background read attempted from control terminal
        !            70: SIGTTOU        22\*d   background write attempted to control terminal
        !            71: SIGIO  23\*b   i/o is possible on a descriptor (see \fIfcntl\fP(2))
        !            72: SIGXCPU        24      cpu time limit exceeded (see \fIsetrlimit\fP(2))
        !            73: SIGXFSZ        25      file size limit exceeded (see \fIsetrlimit\fP(2))
        !            74: SIGVTALRM      26      virtual time alarm (see \fIsetitimer\fP(2))
        !            75: SIGPROF        27      profiling timer alarm (see \fIsetitimer\fP(2))
        !            76: .fi
        !            77: .PP
        !            78: The starred signals in the list above cause a core image
        !            79: if not caught or ignored.
        !            80: .PP
        !            81: If
        !            82: .I func
        !            83: is SIG_DFL, the default action
        !            84: for signal
        !            85: .I sig
        !            86: is reinstated; this default is termination
        !            87: (with a core image for starred signals)
        !            88: except for signals marked with \*b or \*d.
        !            89: Signals marked with \*b are discarded if the action
        !            90: is SIG_DFL; signals marked
        !            91: with \*d cause the process to stop.
        !            92: If
        !            93: .I func
        !            94: is SIG_IGN the signal is subsequently ignored
        !            95: and pending instances of the signal are discarded.
        !            96: Otherwise, when the signal occurs
        !            97: further occurences of the signal are
        !            98: automatically blocked and
        !            99: .I func
        !           100: is called.
        !           101: .PP
        !           102: A return from the function unblocks
        !           103: the handled signal and
        !           104: continues the process at the point it was interrupted.
        !           105: \fBUnlike previous signal facilities, the handler \fIfunc\fP
        !           106: remains installed after a signal has been delivered.\fP
        !           107: .PP
        !           108: If a caught signal occurs
        !           109: during certain system calls, causing
        !           110: the call to terminate prematurely, the call
        !           111: is automatically restarted.
        !           112: In particular this can occur
        !           113: during a
        !           114: .I read
        !           115: or
        !           116: .IR write (2)
        !           117: on a slow device (such as a terminal; but not a file)
        !           118: and during a
        !           119: .IR wait (2).
        !           120: .PP
        !           121: The value of
        !           122: .I signal
        !           123: is the previous (or initial)
        !           124: value of
        !           125: .I func
        !           126: for the particular signal.
        !           127: .PP
        !           128: After a
        !           129: .IR fork (2)
        !           130: or
        !           131: .IR vfork (2)
        !           132: the child inherits
        !           133: all signals.
        !           134: .IR  Execve (2)
        !           135: resets all caught signals to the default action;
        !           136: ignored signals remain ignored.
        !           137: .SH "RETURN VALUE
        !           138: The previous action is returned on a successful call.
        !           139: Otherwise, \-1 is returned and 
        !           140: .I errno
        !           141: is set to indicate the error.
        !           142: .SH ERRORS
        !           143: .I Signal
        !           144: will fail and no action will take place if one of the
        !           145: following occur:
        !           146: .TP 15
        !           147: [EINVAL]
        !           148: .I Sig
        !           149: is not a valid signal number.
        !           150: .TP 15
        !           151: [EINVAL]
        !           152: An attempt is made to ignore or supply a handler for SIGKILL
        !           153: or SIGSTOP.
        !           154: .TP 15
        !           155: [EINVAL]
        !           156: An attempt is made to ignore SIGCONT (by default SIGCONT
        !           157: is ignored).
        !           158: .SH "SEE ALSO"
        !           159: kill(1),
        !           160: ptrace(2), kill(2),
        !           161: sigvec(2), sigblock(2), sigsetmask(2), sigpause(2),
        !           162: sigstack(2), setjmp(3), tty(4)
        !           163: The handler routine can be declared:
        !           164: .PP
        !           165:     handler(sig, code, scp)
        !           166: .PP
        !           167: Here
        !           168: .I sig
        !           169: is the signal number, into which the hardware faults and traps are
        !           170: mapped as defined below.  Code is a parameter which is either a constant
        !           171: as given below or, for compatibility mode faults, the code provided by
        !           172: the hardware. 
        !           173: .I Scp
        !           174: is a pointer to the
        !           175: .I "struct sigcontext"
        !           176: used by the system to restore the process context from before
        !           177: the signal.
        !           178: Compatibility mode faults are distinguished from the
        !           179: other SIGILL traps by having PSL_CM set in the psl.
        !           180: .PP
        !           181: The following defines the mapping of hardware traps to signals
        !           182: and codes.  All of these symbols are defined in
        !           183: .RI < signal.h >:
        !           184: .LP
        !           185: .ta \w'     Floating divide by zero fault  'u +\w'15*  'u +8n
        !           186: .nf
        !           187:    Hardware condition  Signal  Code
        !           188: 
        !           189: Arithmetic traps:
        !           190:    Integer overflow    SIGFPE  FPE_INTOVF_TRAP
        !           191:    Integer division by zero    SIGFPE  FPE_INTDIV_TRAP
        !           192:    Floating overflow trap      SIGFPE  FPE_FLTOVF_TRAP
        !           193:    Floating division by zero   SIGFPE  FPE_FLTDIV_TRAP
        !           194:    Floating underflow trap     SIGFPE  FPE_FLTUND_TRAP
        !           195:    Subscript-range     SIGFPE  FPE_SUBRNG_TRAP
        !           196:    Floating overflow fault     SIGFPE  FPE_FLTOVF_FAULT
        !           197:    Floating divide by zero fault       SIGFPE  FPE_FLTDIV_FAULT
        !           198:    Floating underflow fault    SIGFPE  FPE_FLTUND_FAULT
        !           199: Length access control  SIGSEGV
        !           200: Protection violation   SIGBUS
        !           201: Reserved instruction   SIGILL  ILL_RESAD_FAULT
        !           202: Reserved operand       SIGILL  ILL_PRIVIN_FAULT
        !           203: Reserved addressing    SIGILL  ILL_RESOP_FAULT
        !           204: Trace pending  SIGTRAP
        !           205: Bpt instruction        SIGTRAP
        !           206: .fi

This archive runs on limited infrastructure. Preserving old code on modern bandwidth. Automated agents are requested to crawl responsibly.