Errorhandling Bash Script

Question

I'm not a master in Scripting, so I have to ask here :)

How can I implement an errorhandling for this:

find . -type f|sed 's_\.\/__' > $PATH

i.e. abort when this was not successfull.

Thank you very much in advance Thomas

Can you define `this was not successful`? Regarding `find` or `sed`? — fedorqui, Sep 11 '13 at 11:18
You appear to be using the `PATH` variable to store a file name. Don't; it's a built-in shell parameter that stores a list of directories for command lookup. Use a different variable name. — chepner, Sep 11 '13 at 13:30

Grzegorz Wolny · Answer 1 · 2013-09-11T11:31:18.913

1

try to use conditions like && or ||

find . -type f|sed 's_./__' > $PATH && if_true_do_something || if_false_do_something

edited Sep 11 '13 at 11:31

answered Sep 11 '13 at 11:22

Grzegorz Wolny

11
4

konsolebox · Answer 2 · 2013-09-11T11:52:26.597

First thing is your command would fail at least most certainly since $PATH is an invalid single path.

find . -type f | sed 's_\.\/__' > $PATH

If you want to check if both commands worked well, use the pipefail option which would make a pipe call return a nonzero status if any of the commands along the line return one, not just the last one.

set -o pipefail  ## You have this only once in the script.

find . -type f | sed 's_\.\/__'  > $PATH || {
    echo "Failed."
    exit 1  ## This probably is what you mean to abort.
}

# Shell script continues here...

An alternative:

...
find . -type f | sed 's_\.\/__' > $PATH
if [[ $? -ne 0 ]]; then
    echo "Failed."
    exit 1
fi

Example:

> set +o pipefail  ## Disable pipefail (default).
> true | false
> echo $?
1
> false | true
> echo $?
0

> set -o pipefail  ## Enable pipefail.
> true | false
> echo $?
1
> false | true
> echo $?
1

Notice that the last command returned 1 even if false was not at the end. While when pipefail was disabled, the pipe command would still return 0 even though one of the commands (false) returned 1.

Errorhandling Bash Script

2 Answers2