If you’re trying to use the find binary in your Bash Scripts, and are creating your parameters in your scripts, you can run into the following problem when executing it.
/usr/bin/find: paths must precede expression Usage: /usr/bin/find [-H] [-L] [-P] [path...] [expression]
Even though if you copy/paste the find-string into your current shell and execute it, the find command works just fine. This can happen when you’re nesting expressions like such:
#!/bin/bash # Create your variable FIND_EXEC="find '/home/mattias/data/' -not \( \( -path '/home/mattias/data/production/*' -prune \) -o \( -path '/home/mattias/data/testing/*' -prune \) \)" # Run it $FIND_EXEC
When trying to run that through a bash-shell, you’ll get the following output.
# ./testFind.sh find: paths must precede expression Usage: find [-H] [-L] [-P] [path...] [expression]
Even though if you execute the entire find command, it works like a charm. The problem lies within Bash’ way of escaping data, which gets complicated when your find command already has escaped data in it. If you still want to use the find variable you just created ($FIND_EXEC in my example), you can run it with the eval keyword in front of it.
#!/bin/bash # Create your variable FIND_EXEC=">find '/home/mattias/data/' -not \( \( -path '/home/mattias/data/production/*' -prune \) -o \( -path '/home/mattias/data/testing/*' -prune \) \)" # Run it, with eval this time eval $FIND_EXEC
Which works just fine when you run it.
# ./testFind.sh /home/mattias/data/ /home/mattias/data/testFind_ignore.txt /home/mattias/data/includes ...
That’s a line I won’t soon forget.