NAME
signal
- signal facilities
DESCRIPTION
The
<
signal.h
>
header file defines the following signals:
Value Name Default Action Description
| 1 |
SIGHUP terminate process terminal line hangup
| 2 |
SIGINT terminate process interrupt program
| 3 |
SIGQUIT create core image quit program
| 4 |
SIGILL create core image illegal instruction
| 5 |
SIGTRAP create core image trace trap
| 6 |
SIGABRT create core imageabort(3)
call (formerly
SIGIOT )
| 7 |
SIGEMT create core image emulate instruction executed
| 8 |
SIGFPE create core image floating-point exception
| 9 |
SIGKILL terminate process kill program (cannot be caught or ignored)
| 10 |
SIGBUS create core image bus error
| 11 |
SIGSEGV create core image segmentation violation
| 12 |
SIGSYS create core image invalid system call argument
| 13 |
SIGPIPE terminate process write to a pipe with no reader
| 14 |
SIGALRM terminate process real-time timer expired
| 15 |
SIGTERM terminate process software termination signal
| 16 |
SIGURG discard signal urgent condition present on socket
| 17 |
SIGSTOP stop process stop (cannot be caught or ignored)
| 18 |
SIGTSTP stop process stop signal generated from keyboard
| 19 |
SIGCONT discard signal continue after stop
| 20 |
SIGCHLD discard signal child status has changed
| 21 |
SIGTTIN stop process background read attempted from control terminal
| 22 |
SIGTTOU stop process background write attempted to control terminal
| 23 |
SIGIO discard signal I/O is possible on a descriptor (see
fcntl(2))
| 24 |
SIGXCPU terminate process CPU time limit exceeded (see
setrlimit(2))
| 25 |
SIGXFSZ terminate process file size limit exceeded (see
setrlimit(2))
| 26 |
SIGVTALRM terminate process virtual time alarm (see
setitimer(2))
| 27 |
SIGPROF terminate process profiling timer alarm (see
setitimer(2))
| 28 |
SIGWINCH discard signal window size change
| 29 |
SIGINFO discard signal status request from keyboard
| 30 |
SIGUSR1 terminate process user-defined signal 1
| 31 |
SIGUSR2 terminate process user-defined signal 2
| 32 |
SIGPWR discard signal power failure/restart
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
A function that is async-signal-safe is either reentrant or
non-interruptible by signals.
This means that they can be used in
signal handlers
and in the child of threaded programs after doing
fork(2).
The following functions are async-signal-safe.
Any function not listed
below is unsafe to use in signal handlers.
_Exit(2),
_exit(2),
abort(3),
accept(2),
access(2),
alarm(3),
bind(2),
cfgetispeed(3),
cfgetospeed(3),
cfsetispeed(3),
cfsetospeed(3),
chdir(2),
chmod(2),
chown(2),
clock_gettime(2),
close(2),
connect(2),
creat(3),
dup(2),
dup2(2),
execle(3),
execve(2),
fchmod(2),
fchown(2),
fcntl(2),
fdatasync(2),
fork(2),
fpathconf(2),
fstat(2),
fsync(2),
ftruncate(2),
getegid(2),
geteuid(2),
getgid(2),
getgroups(2),
getpeername(2),
getpgrp(2),
getpid(2),
getppid(2),
getsockname(2),
getsockopt(2),
getuid(2),
kill(2),
link(2),
listen(2),
lseek(2),
lstat(2),
mkdir(2),
mkfifo(2),
open(2),
pathconf(2),
pause(3),
pipe(2),
poll(2),
raise(3),
read(2),
readlink(2),
recv(2),
recvfrom(2),
recvmsg(2),
rename(2),
rmdir(2),
select(2),
sem_post(3),
send(2),
sendmsg(2),
sendto(2),
setgid(2),
setpgid(2),
setsid(2),
setsockopt(2),
setuid(2),
shutdown(2),
sigaction(2),
sigaddset(3),
sigdelset(3),
sigemptyset(3),
sigfillset(3),
sigismember(3),
sleep(3),
signal(3),
sigpause(3),
sigpending(2),
sigprocmask(2),
sigset(3),
sigsuspend(2),
sockatmark(3),
socket(2),
socketpair(2),
stat(2),
symlink(2),
sysconf(3),
tcdrain(3),
tcflow(3),
tcflush(3),
tcgetattr(3),
tcgetpgrp(3),
tcsendbreak(3),
tcsetattr(3),
tcsetpgrp(3),
time(3),
timer_getoverrun(2),
timer_gettime(2),
timer_settime(2),
times(3),
umask(2),
uname(3),
unlink(2),
utime(3),
wait(2),
waitpid(2),
write(2).
STANDARDS
These signals conform to
ISO/IEC 9945-1:1990 (``POSIX.1'') ,
with the exception of
SIGTRAP
,
SIGEMT
,
SIGBUS
,
SIGSYS
,
SIGURG
,
SIGIO
,
SIGXCPU
,
SIGXFSZ
,
SIGVTALRM
,
SIGPROF
,
SIGWINCH
,
and
SIGINFO
which are Berkeley extensions (available on most
NsBSD-derived
systems), and
SIGPWR
which comes from System V.
HISTORY
SIGPWR
was introduced in
NetBSD1.4.
NOTES
The current
NetBSD
kernel never generates the
SIGPWR
signal.
SEE ALSO
kill(1),
kill(2),
ptrace(2),
sigaction(2),
sigaltstack(2),
sigprocmask(2),
sigstack(2),
sigsuspend(2),
fpgetmask(3),
fpsetmask(3),
setjmp(3),
sigblock(3),
siginterrupt(3),
signal(3),
sigpause(3),
sigsetmask(3),
sigsetops(3),
tty(4)