Linux Shell script what dirname and ? means?

bash, linux, unix

Solution

The dirname command removes the trailing / component from the NAME and prints the remaining portion. If the NAME does not contain / component then it prints '.' (means current directory)

Dirname Command Example:

Remove the file name from absolute path.

Let say my directory path is /usr/local/bin/add.sh. Now i want to remove /add.sh and display only /usr/local/bin, then we can use the dirname command.

dirname /usr/local/bin/add.sh
/usr/local/bin

NAME

`dirname` - strip non-directory suffix from file name

SYNOPSIS

dirname NAME 
dirname OPTION

DESCRIPTION

Print NAME with its trailing /component removed; if NAME contains no /’s, output ‘.’ (meaning the current directory).

Edit: Also, Some characters have special functions in linux commands `?` <-- Matches one character

Source

Problem

Can any body tell me what this command means? ``` selfDir=$(cd "$(dirname "$0")"; pwd) ? ``` I know - `$0` = running script name - `pwd` = current working dir - `cd` = to change dir What I need is what is dirname? and what ? means at end to make this line completely understandable.

Original source