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Bash Exit On Any Error


PROGNAME=$(basename $0) function error_exit { # ---------------------------------------------------------------- # Function for exit due to fatal program error # Accepts 1 argument: # string containing descriptive error message # ---------------------------------------------------------------- echo "${PROGNAME}: ${1:-"Unknown I have added a for loop to pause for a few seconds then retry the curl command use false at the bottom of the for loop to define a default non-zero It is, though, a question of style and others can have their own opinions. –John1024 Nov 6 '15 at 7:37 1 works nicely! When we execute this script (as a non-root user) the touch command will fail, ideally since the touch command failed we would want the exit code of the script to indicate this contact form

echo 'Bad: has not aborted execution on syntax error!' Result: $ ./sh-on-syntax-err ./sh-on-syntax-err: line 6: #: syntax error: operand expected (error token is "#") status 1 Bad: has not aborted execution That usage is simply a style thing. In that case, the shell will interpret the variable as empty and the cd succeed, but it will change directories to the user's home directory, so beware! Aborting" rm * If an exit is not required in case of error, then you can even do this: # Another way to do it if exiting is not desired cd

Bash Shell Exit On Error

There are several things you can do to prevent errors in these situations. set -e errexit set -o pipefail -e (errexit): Abort script at first error, when a command exits with non-zero status (except in until or while loops, if-tests, list constructs) -o pipefail: share|improve this answer edited Jun 4 '13 at 13:48 fedorqui 108k30164211 answered May 4 '09 at 19:02 lumpynose 74739 15 To potentially save others the need to read through help echo "command failed with exit code $ret" >&2 exit $ret fi share|improve this answer answered Dec 16 '09 at 10:18 Mark Edgar 2,19811615 Why "should always be written as"?

An advantage is that you now have a backup before you made your changes in case you need to revert. © 2013 Company Name Advanced Bash-Scripting Guide: Prev

Just do it like this: dosomething1 || exit 1 If you take Ville Laurikari's advice and use set -e then for some commands you may need to use this: dosomething || Be atomic Sometimes you need to update a bunch of files in a directory at once, say you need to rewrite urls form one host to another on your website. there are dark corners in the Bourne shell, and people use all of them.

--Chet Ramey

The exit command terminates a script, This variable will print the exit code of the last run command.

That is why I wrote exit 1 when just plain exit would have worked. Bash Exit On First Error How to pluralize "State of the Union" without an additional noun? asked 7 years ago viewed 97056 times active 9 months ago Linked 0 exit from driver script if child script fails 3 Catch failure in shell script 0 Detecting success or When was this language released?

  1. After a function returns, $? gives the exit status of the last command executed in the function.
  2. Unix & Linux Stack Exchange works best with JavaScript enabled Toggle navigation Benjamin Cane Home Archive RSS Twitter Mail Feed Understanding Exit Codes and how to use them in bash scripts
  3. echo exit 113 # Will return 113 to shell. # To verify this, type "echo $?" after script terminates. # By convention, an 'exit 0' indicates success, #+ while a non-zero

Bash Exit On Error With Message

share|improve this answer edited Apr 23 '14 at 9:13 MattBianco 795721 answered Dec 7 '10 at 21:13 Byron Whitlock 35k1985141 2 If you like the ABS, you'll love the BashGuide, share|improve this answer edited May 7 '09 at 20:58 answered May 7 '09 at 20:52 fholo 366211 add a comment| up vote 11 down vote Run it with -e or set Bash Shell Exit On Error To my surprise, I can't achieve this. (set -e is not enough.) Example: #!/bin/bash # Do exit on any error: set -e readonly a=(1 2) # A syntax error is here: Bash Exit On Error Code The list constructs use exit codes to understand whether a command has successfully executed or not.

You can surround a variable name with curly braces (as with ${PROGNAME}) if you need to be sure it is separated from surrounding text. weblink Using -e gives you error checking for free. thanks :) personally I would read exit as a plain exit - that terminates the script in its own right. EXIT Exit - this is a pseudo-signal and is triggered when your script exits, either through reaching the end of the script, an exit command or by a command failing when Bash Exit Script On Error

Each time expr2 evaluates to a non-zero value, list is executed and the arithmetic expression expr3 is evaluated. Also look at set -u. errexit) - that it should terminate the script based on the "result" of exit 1. - so I have gone with exit but thanks for explanation –the_velour_fog Nov 6 '15 at navigate here It merely tells the calling program that something went wrong.

Not the intended behavior! Bash Exit Status Variable That does not affect errexit at all. Exit status As you recall from previous lessons, every well-written program returns an exit status when it finishes.

Will the medium be able to last 100 years?

share|improve this answer answered Dec 8 '10 at 5:12 Dennis Williamson 167k42235305 add a comment| up vote 2 down vote Here is the way to do it: #!/bin/sh abort() { echo An AND list has the form command1 && command2 command2 is executed if, and only if, command1 returns an exit status of zero. asked 3 years ago viewed 6520 times active 3 years ago Linked 4 How to write an abort-on-error script without adding `|| exit $?` to every line? Bash Exit On Failure inverts the exit status returned.

share|improve this answer answered May 20 '10 at 4:34 sth 127k33203307 More information here: davidpashley.com/articles/… –dhornbein Jun 13 '13 at 3:39 add a comment| up vote 27 down vote The lockfile will be left there and your script won't run again until it's been deleted. Why write an entire bash script in functions? his comment is here If the exit code of ./tmp.sh is 1 however, the commands within the parenthesis will be executed next.

Join them; it only takes a minute: Sign up Automatic exit from bash shell script on error up vote 276 down vote favorite 48 I've been writing some shell script and set +e command1 command2 set -e On a slightly related note, by default bash takes the error status of the last item in a pipeline, which may not be what you If you add a -p option then mkdir will create all the parent directories before creating the requested directory. command; then echo "command failed"; exit 1; fi What if you have a command that returns non-zero or you are not interested in its return value?