I've been writing some shell script and I would find it useful if there was the ability to halt the execution of said shell script if any of the commands failed. See below for an example:
#!/bin/bash
cd some_dir
./configure --some-flags
make
make install
So in this case, if the script can't change to the indicated directory, then it would certainly not want to do a ./configure afterwards if it fails.
Now I'm well aware that I could have an if check for each command (which I think is a hopeless solution), but is there a global setting to make the script exit if one of the commands fails?
Use the set -e
builtin:
#!/bin/bash
set -e
# Any subsequent(*) commands which fail will cause the shell script to exit immediately
Alternatively, you can pass -e
on the command line:
bash -e my_script.sh
You can also disable this behavior with set +e
.
You may also want to employ all or some of the the -e
-u
-x
and -o pipefail
options like so:
set -euxo pipefail
-e
exits on error, -u
errors on undefined variables, -x
prints commands before execution, and -o (for option) pipefail
exits on command pipe failures. Some gotchas and workarounds are documented well here.
(*) Note:
The shell does not exit if the command that fails is part of the command list immediately following a while or until keyword, part of the test following the if or elif reserved words, part of any command executed in a && or || list except the command following the final && or ||, any command in a pipeline but the last, or if the command's return value is being inverted with !
(from man bash
)