POSIX 定义的信号
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信号 值 动作 注释
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SIGHUP 1 A Hangup detected on controlling terminal
or death of controlling process
SIGINT 2 A Interrupt from keyboard
SIGQUIT 3 A Quit from keyboard
SIGILL 4 A Illegal Instruction
SIGABRT 6 C Abort signal from abort(3)
SIGFPE 8 C Floating point exception
SIGKILL 9 AEF Kill signal
SIGSEGV 11 C Invalid memory reference
SIGPIPE 13 A Broken pipe: write to pipe with no readers
SIGALRM 14 A Timer signal from alarm(2)
SIGTERM 15 A Termination signal
SIGUSR1 30,10,16 A User-defined signal 1
SIGUSR2 31,12,17 A User-defined signal 2
SIGCHLD 20,17,18 B Child stopped or terminated
SIGCONT 19,18,25 Continue if stopped
SIGSTOP 17,19,23 DEF Stop process
SIGTSTP 18,20,24 D Stop typed at tty
SIGTTIN 21,21,26 D tty input for background process
SIGTTOU 22,22,27 D tty output for background process
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* 信号值是 Linux 系统在不同平台上的取值, 第一个数对 Alpha 和 Sparc 有效, 中
间的数对 i386 和 PowerPC 有效, 最后一个数对 MIPS 有效. "-" 表现缺少该信号.