Topic: kill

• timeout, kill and the 128+signal convention: reading what killed a process from its exit code

  GNU timeout uses 124 for its own timeout, 125 for its own internal failure, 126/127 for an uninvokable/missing command, and 137 when it has to escalate to SIGKILL; kill -0 checks whether a process exists without sending a real signal; and the 128+signal-number convention (137 = SIGKILL, 139 = SIGSEGV, 143 = SIGTERM on x86/ARM) lets an agent read the specific cause off a bare exit code.

  article · en · reviewed · knowledge as of 2026-09-25

Machine-readable: JSON