The exit command when executed from a file being sourced doesn't terminate the execution of the program where it was being sourced, how to do this? Consider this files for a clearer explanation:
a.fish:
source b.fish
echo "This should never run!"
b.fish:
echo "Failing now"
exit 1
This will result in this (undesired output):
Failing now
This should never run!
And the exit status is 0! Is there a solution for B to terminate execution of A as if exit was written in A itself?
It's perfectly working the way you want with bash and zsh. Still, I found a solution for fish:
source b.fish; or exit 1
This will exit a.fish if b.fish exited with exit 1, and will continue otherwise.
Related
Let's say there's this script
#!/bin/zsh
python -c 'a'
which will fail since a isn't defined. Just before the shell script exits, I want to run a command, say echo bye. How can that be achieved?
Flow is to be:
Python command above fails.
bye appears in terminal.
The zsh script exits.
I'd prefer it to affect the python command as little as possible such as indent, putting it in an if block, checking its exit code etc. In real life, the command is in fact multiple commands.
In the script you posted, the fact that the shell exits is unrelated to any error. The shell would exit, because the last argument hast been executed. Take for instance the script
#!/bin/zsh
python -c 'a'
echo This is the End
The final echo will always be exeuted, independent of the python command. To cause the script to exit, when python returns a non-zero exit code, you would write something like
#!/bin/zsh
python -c 'a' || exit $?
echo Successful
If you want to exit a script, whenever the first one of the commands produces a non-zeror exit status, AND at the same time want to print a message, you can use the TRAPZERR callback:
#!/bin/zsh
TRAPZERR() {
echo You have an unhandled non-zero exit code in your otherwise fabulous script
exit $?
}
python -c 'a'
echo Only Exit Code 0 encountered
recently came across an issue when running a bash script executed in a csh shell. This was outputed: /bin/bash: bad interpreter: No such file or directory. The problem was bash was not on the environment path. After adding bash, this was fixed. I want to make sure that in the future, if this ever happened again for some reason, I can handle this. I am wonder what exit code this is? or is this just printed out on stderr? I want to catch this and fail the main script. Any ideas on how to handle this?
I have this segment:
bash sc142.sh
#####################################################################
# Check for processing errors
#####################################################################
if ($status != 0) then
exit (-1)
endif
I tried this on Debian, the exit status for a bad interpreter error is 126. So you can do:
/path/to/scriptname arg ...
if ( $status == 126 ) then
echo "scriptname failed"
exit 1
endif
Note that a false positive is possible. If the last command in the script you're running exits with status 126, you won't be able to tell the difference.
The exit code will be non-zero. The exact exit code depends on the environment. You may get 127 (command not found) but you may also get another non-zero exit code in certain shells.
In your csh script you can set the -e option which will cause the script to exit immediately if any commands fail.
#!/bin/csh -e
false
echo not printed
I have a shell script installed to run every day.
The script consists of some rm (delete) commands and SCP commands for file transfer. The script is failing due to some errors in production. I want the job to return exit code as 0 without executing anything, so I wrote
exit 0;
at the beginning of the shell script so that as soon as the script executes, it will exit with out any commands after that exit 0; but still the script is failing.
I cannot edit the whole contents inside the file nor delete the script or contents inside the script.
Please suggest whether I am using the right syntax for exit command or how to make the script to exit with return code 0 as soon as it starts executing.
The ';' is unnecessary. You can exit like this:
exit
exit 1
This is a description about 'Exit and Exit Status'.
I am running an sh script as part of my .travis.yml. It is giving me the error below although the shell script does not fail.
The command exited with 1.
I tried running the with bash -x to debug and there are no errors.
The problem is that travis thinks that the build failed although it passed.
This change fixes it.
As explained in the man bash page:
Shell builtin commands return a status of 0 (true) if successful, and
non-zero (false) if an error
occurs while they execute. All builtins return an exit status of 2 to indicate incorrect usage.
Bash itself returns the exit status of the last command executed,
unless a syntax error occurs, in which case it exits with a non-zero
value. See also the exit builtin command below.
The last command executed is:
[ "$BUILD_CHROMIUM" == 1 ] &&_build_chromium_crx "${zip_file}" "${BUILD_METADATA[${CHROMIUM_TARGET}]}"
And it is evaluated as false with exit status 1:
'[' 0 == 1 ']'
So adding || true at the end of this line fixes it. The exit status will always be 0.
Alternatively, use the fix that better suits the expected behavior of your code like exit 0, etc.
As explained here and here:
exit [n] Cause the shell to exit with a status of n. If n is omitted,
the exit status is that of the last command executed. A trap on EXIT
is executed before the shell terminates.
So your clean function trap _clean_chrome EXIT is not the last to be executed.
Further information about exit status here.
I have a main script. Inside it I call other three shell scripts, A,B and C. All were successful. Exit codes are all equal to zero. However, when I looked into the output file of the first script which is A, it contains an error message. Now I want to exit the main script and not to continue running the other scripts after the script that has output error. Can anyone help me on this? Thanks!
Even if some command in your first bash script results in an error, the script as a whole may complete with exit code 0.
You can check the exit code of any individual command in your script by using the $? variable. This variable stores the exit code of the previous command. This will allow you to check for errors within the script.
The easiest way is to append || exit 1 to the statement which is throwing the error. That will cause the script to exit if the exit code of the command is 1 (i.e. an error).
So assuming you had a command sqlscript and you wanted the entire script to exit if sqlscript exited with a non-zero exit code you would do
sqlscript || exit 1
As a point of trivia, the 1 in exit 1 is not needed. A plain exit command would also exit with the exit status of the last executed command.
Which would be false (code=1) if the sqlscript command fails. If the sqlscript command succeeds, the exit code is the exit code of sqlscript. In that case, the || does not trigger and the exit command is not executed.
I have a main script. Inside it I call other three shell scripts, A,B
and C. All were successful. Exit codes are all equal to zero. However,
when I looked into the output file of the first script which is A, it
contains an error message. Now I want to exit the main script and not
to continue running the other scripts after the script that has output
error.
Since script A doesn't return an error exit code, you have to inspect its output. This is quite easy with grep provided that you have a search string which clearly identifies an error message, e. g.:
# this echo command simulates script A - it outputs "error" and exits with 0:
echo "contains an error message" >StoreKey_All.csv # assumed this output file
grep error StoreKey_All.csv && exit 1 # exit if output has error
# continue with scripts B and C
echo B