Published: October 21, 2022 • 2 min read
The exit code of a command in a Unix-based system is an important and easy-to-miss piece of data. It isn’t printed to standard out; you have to go looking for it. I find it useful to inspect this information when debugging or considering chaining unfamiliar commands.
To see the exit code of your last command, echo its variable ($
) value:
$ echo "something"
"something"
$ echo $?
0 # Success!
# '1' example
$ rm nonexistent-file
rm: nonexistent-file: No such file or directory
$ echo $?
1 # Failure.
The two exit codes you must remember are 0
, command was successful, and 1
,
a catch-all for errors. Zero is success, not-zero failure.
I have a terminal function that prints this variable:
# Print the last exit status
function print_status() {
echo $?
}
What are your thoughts on this? Let me know!
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