How to get full path of a file?

I suppose you are using Linux.

I found a utility called realpath in coreutils 8.15.

realpath file.txt
/data/ail_data/transformed_binaries/coreutils/test_folder_realpath/file.txt

As per @styrofoam-fly and @arch-standton comments, realpath alone doesn't check for file existence, to solve this add the e argument: realpath -e file

The following usually does the trick:

 echo "$(cd "$(dirname "$1")" && pwd -P)/$(basename "$1")"

I know there's an easier way that this, but darned if I can find it...

[email protected]:~$ python -c 'import os; print(os.path.abspath("cat.wav"))'
/home/jcomeau/cat.wav

[email protected]:~$ ls $PWD/cat.wav
/home/jcomeau/cat.wav

find $PWD -type f | grep "filename"

or

find $PWD -type f -name "*filename*"

If you are in the same directory as the file:

ls "`pwd`/file.txt"

Replace file.txt with your target filename.