mjhjmtu

name=$(echo "$FILENAME" | grep -E '*.(eng|por|pt-BR).*')

Why this line doesn't work?

if I do

echo "Test (2013).1080p.por.mkv" | grep -E "*.(eng|por).*"

It works, I tried with "" without " and with ' in my script and it seems like it's not getting piped to grep. I don't know why? I'm using bash.

FILENAME="Test (2013).1080p.por.mkv"

I want to grab only .por. or .eng in a file

grep is the tool to print (whole) lines matching a pattern. It's not appropriate to extract parts of a string (though some grep implementations have -o<n> or -o options that can be used in some cases for that).

Here, you can use expr:

name=$(expr " $FILENAME" : '.*.(eng).' '|' 
 " $FILENAME" : '.*.(por).' '|' 
 " $FILENAME" : '.*.(pt-PT).')

(for foo.por.eng.bar, gives priority to eng over por over pt-PT).

Some expr implementations like GNU expr also support:

name=$(expr " $FILENAME" : '.*.(eng|por|pt-PT).')

(here returns the rightmost occurrence if there are several in the filename)

With GNU grep or compatible:

name=$(
 printf '%sn' "$FILENAME" |
 grep -Po '.K(eng|por|pt-PT)(?=.)' |
 head -n 1
)

(returns first occurrence, replace head with tail for last)

Or you could use your shell's case construct and not run any command at all:

case $FILENAME in
 (*.por.*) name=por;;
 (*.eng.*) name=eng;;
 (*.pt-PT.*) name=pt-PT;;
esac

With bash:

re='.(por|eng|pt-PT).'
[[ $FILENAME =~ $re ]]
name=$BASH_REMATCH[1]

(first occurrence. With zsh, replace BASH_REMATCH with match)

Assuming the file names are like Some name.por.mkv, with the final extension fixed, you could use the POSIX shell string operations, too:

$ echo "$FILENAME"
Test (2013).1080p.por.mkv
$ x=$FILENAME%.mkv; echo "$x##*."
por

Here, $var%.mkv removes the trailing .mkv, and $var##*. removes everything up to the (now) last dot. You could change the first expansion to handle other extensions by changing .mkv to just .*.