Exit Codes Reference
Look up shell and Unix process exit codes — 0 success, 1/2 errors, 126/127/128/255 special shell codes, the 128+N fatal-signal range (130 SIGINT, 137 SIGKILL, 139 SIGSEGV, 143 SIGTERM) and the BSD sysexits.h codes (64–78). Search, filter and copy. In your browser, free.
Every standard shell and Unix exit (return) code, explained. Everything runs in your browser from a built-in reference — nothing is sent to the server.
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About Exit Codes Reference
The Exit Codes Reference explains the numeric status a shell or Unix process returns when it ends. It covers the full landscape: 0 for success, 1 and 2 for general errors, the special shell codes 126 (found but not executable), 127 (command not found), 128 (invalid exit argument) and 255 (out of range), the 128+N fatal-signal range, and the BSD sysexits.h codes 64–78.
The signal range is where most head-scratching happens: 130 means the process was interrupted with Ctrl+C (SIGINT), 137 means it was force-killed (SIGKILL — often the out-of-memory killer in containers), 139 is a segmentation fault (SIGSEGV) and 143 is a polite termination (SIGTERM). Each entry names the signal and explains what typically triggers it.
Search by number, signal or sysexits name, or plain-language meaning; filter by category — Success, General, Shell, Signal or sysexits.h — and copy any code with a click. Everything runs from a built-in reference in your browser.
How to use Exit Codes Reference
- Type an exit code (137), a name (SIGSEGV, EX_USAGE) or a phrase like “command not found” into the search box.
- Filter by category if needed: Success, General, Shell, Signal or sysexits.h.
- Read the entry’s meaning and description; signal-range entries also name the underlying signal.
- Copy the code for a bug report, monitoring rule or script comparison.