splitting the string in bash script

Question

I am taking some input from user and checking details about that.

Example:

$HOME/Documents/test/one.txt

I take the above string as an input and want to retrieve one.txt, I need to further proceed with one.txt.

Answer 1

@Jordanm has already given you the canonical answer that works for any string. If you are dealing specifically with paths, you can also use the programs basename and dirname:

   basename - strip directory and suffix from filenames
   dirname - strip last component from file name

For example:

$ file="$HOME/Documents/test/one.txt"
$ dir=$(dirname "$file");
$ name=$(basename "$file");
$ echo "The file called $name is in the directory $dir"
The file called one.txt is in the directory /home/terdon/Documents/test

Answer 2

This is a common task that can be handled by a parameter expansion in any POSIX shell.

path=$HOME/Documents/test/one.txt
file=${path##*/} # file contains one.txt

Another common method is to use the basename program.

file=$(basename "$path")

The only disadvantage is having to spawn an external program. It's main advantage is that it properly handles paths with a trailing /.

Answer 3

If you're doing this with filenames, use the basename command:

$ basename $HOME/Documents/test/one.txt
one.txt

Further:

$ FILE=$(basename basename $HOME/Documents/test/one.txt)
$ echo $FILE
one.txt

If you need to split arbitrary strings with arbitrary delimiters it's a little bit of magic. Read the string into an array and set the input field separator to the delimiter.

Here's an example:

$ IFS='/' read -a my_array <<< "$HOME/Documents/test/one.txt"
$ ARRAY_LENGTH=$(( ${#my_array[@]} - 1 ))
$ echo "${my_array[$ARRAY_LENGTH]}"
one.txt