Unix 訊號定義
在 unix 中的每個信號號都有對應的定義，決定了當進程接收到信號時的行為。下面表格中的 Action 列條目指定了每個信號的默認處置。
- Ign：Default action is to ignore the signal.
- Core：Default action is to terminate the process and dump core (see core(5)).
- Stop：Default action is to stop the process.
- Cont：Default action is to continue the process if it is currently stopped.
Refencers
https://man7.org/linux/man-pages/man7/signal.7.html
Standard signals
| Signal | Standard | Action | Comment |
|---|---|---|---|
| SIGABRT | P1990 | Core | Abort signal from abort(3) |
| SIGALRM | P1990 | Term | Timer signal from alarm(2) |
| SIGBUS | P2001 | Core | Bus error (bad memory access) |
| SIGCHLD | P1990 | Ign | Child stopped or terminated |
| SIGCLD | - | Ign | A synonym for SIGCHLD |
| SIGCONT | P1990 | Cont | Continue if stopped |
| SIGEMT | - | Term | Emulator trap |
| SIGFPE | P1990 | Core | Erroneous arithmetic operation |
| SIGHUP | P1990 | Term | Hangup detected on controlling terminal or death of controlling process |
| SIGILL | P1990 | Core | Illegal Instruction |
| SIGINFO | - | A synonym for SIGPWR | |
| SIGINT | P1990 | Term | Interrupt from keyboard |
| SIGIO | - | Term | I/O now possible (4.2BSD) |
| SIGIOT | - | Core | IOT trap. A synonym for SIGABRT |
| SIGKILL | P1990 | Term | Kill signal |
| SIGLOST | - | Term | File lock lost (unused) |
| SIGPIPE | P1990 | Term | Broken pipe: write to pipe with no readers; see pipe(7) |
| SIGPOLL | P2001 | Term | Pollable event (Sys V); synonym for SIGIO |
| SIGPROF | P2001 | Term | Profiling timer expired |
| SIGPWR | - | Term | Power failure (System V) |
| SIGQUIT | P1990 | Core | Quit from keyboard |
| SIGSEGV | P1990 | Core | Invalid memory reference |
| SIGSTKFLT | - | Term | Stack fault on coprocessor (unused) |
| SIGSTOP | P1990 | Stop | Stop process |
| SIGTSTP | P1990 | Stop | Stop typed at terminal |
| SIGSYS | P2001 | Core | Bad system call (SVr4); see also seccomp(2) |
| SIGTERM | P1990 | Term | Termination signal |
| SIGTRAP | P2001 | Core | Trace/breakpoint trap |
| SIGTTIN | P1990 | Stop | Terminal input for background process |
| SIGTTOU | P1990 | Stop | Terminal output for background process |
| SIGUNUSED | - | Core | Synonymous with SIGSYS |
| SIGURG | P2001 | Ign | Urgent condition on socket (4.2BSD) |
| SIGUSR1 | P1990 | Term | User-defined signal 1 |
| SIGUSR2 | P1990 | Term | User-defined signal 2 |
| SIGVTALRM | P2001 | Term | Virtual alarm clock (4.2BSD) |
| SIGXCPU | P2001 | Core | CPU time limit exceeded (4.2BSD); see setrlimit(2) |
| SIGXFSZ | P2001 | Core | File size limit exceeded (4.2BSD); see setrlimit(2) |
| SIGWINCH | - | Ign | Window resize signal (4.3BSD, Sun) |