各个信号的解释

利用man 7 signal可以查看各个信号的基本解释.

SIGHUP 1 Term Hangup detected on controlling terminal

or death of controlling process

SIGINT 2 Term Interrupt from keyboard

SIGQUIT 3 Core Quit from keyboard

SIGILL 4 Core Illegal Instruction

SIGABRT 6 Core Abort signal from abort(3)

SIGFPE 8 Core Floating point exception

SIGKILL 9 Term Kill signal

SIGSEGV 11 Core Invalid memory reference

SIGPIPE 13 Term Broken pipe: write to pipe with no readers

SIGALRM 14 Term Timer signal from alarm(2)

SIGTERM 15 Term Termination signal

SIGUSR1 30,10,16 Term User-defined signal 1

SIGUSR2 31,12,17 Term User-defined signal 2

SIGCHLD 20,17,18 Ign Child stopped or terminated

SIGCONT 19,18,25 Cont Continue if stopped

SIGSTOP 17,19,23 Stop Stop process

SIGTSTP 18,20,24 Stop Stop typed at tty

SIGTTIN 21,21,26 Stop tty input for background process

SIGTTOU 22,22,27 Stop tty output for background process

The signals SIGKILL and SIGSTOP cannot be caught, blocked, or ignored.

Next the signals not in the POSIX.1-1990 standard but described in SUSv2 and POSIX.1-2001.

Signal Value Action Comment

-------------------------------------------------------------------------

SIGBUS 10,7,10 Core Bus error (bad memory access)

SIGPOLL Term Pollable event (Sys V). Synonym of SIGIO

SIGPROF 27,27,29 Term Profiling timer expired

SIGSYS 12,-,12 Core Bad argument to routine (SVr4)

SIGTRAP 5 Core Trace/breakpoint trap

SIGURG 16,23,21 Ign Urgent condition on socket (4.2BSD)

SIGVTALRM 26,26,28 Term Virtual alarm clock (4.2BSD)

SIGXCPU 24,24,30 Core CPU time limit exceeded (4.2BSD)

SIGXFSZ 25,25,31 Core File size limit exceeded (4.2BSD)