Exit Code Glossary
Exit Code
An exit code is a small status number returned by a program when it finishes: conventionally 0 means success, while a non-zero value means some other outcome or failure.
The number lets software judge software. A human may read the words printed on screen; an automation system usually looks first at the exit code. If it is non-zero, the surrounding tool may summarize the event as failed.
The convention needs interpretation. A search program may return 1 simply because it found no matching text. That can be expected and harmless, but a generic automation layer may still display a warning. Another code may mean an invalid command, missing file, denied permission, or internal program error.
This is why “command failed” describes a machine-readable outcome, not necessarily the fate of the whole task. A good operator reads the actual error, decides whether it matters, and continues when a safe alternative exists.