Pattern: Malformed precedence for find -o
Issue: -
In find, two predicates with no operator between them is considered a logical, short-circuiting AND (as if using -a). E.g., -name '*.mkv' -exec .. is the same as -name '*.mkv' -a -exec ...
-a has higher precedence than -o, so -name '*.avi' -o -name '*.mkv' -a -exec .. is equivalent to -name '*.avi' -o \( -name '*.mkv' -a -exec .. \).
Example of incorrect code:
find . -name '*.avi' -o -name '*.mkv' -exec cp {} /media \;This means "if name matches *.avi, do nothing. Otherwise, if it matches *.mkv, execute a command.".
Example of correct code:
find . \( -name '*.avi' -o -name '*.mkv' \) -exec cp {} /media \;We use \( \) to group to get the evaluation order we want. The correct code means "if name matches *.avi or *.mkv, then execute a command", which was what was intended.
If you're aware of this, you can either ignore this error or group to make it explicit. For example, to decompress all gz files except tar.gz, you can use:
find . -name '*.tar.gz' -o \( -name '*.gz' -exec gzip -d {} + \)