I need to check if a path contains the \'*\' character as last digit.
My approach:
length=${#filename}
((file
[ "${filename:$length:1}" == "*" ] && echo yes
In your post, there was no space between "*" and ]. This confuses bash. If a statement begins with [, bash insists that its last argument be ]. Without the space, the last argument is "*"] which, after quote removal, becomes *] which is not ].
Putting it all together:
length=${#filename}
((length--))
[ "${filename:$length:1}" == "*" ] && echo yes
MORE: As per the comments below, the three lines above can be simplified to:
[ "${filename: -1}" == "*" ] && echo yes
The -1 is shorthand for getting the last character. Another possibility is:
[[ $filename = *\* ]] && echo yes
This uses bash's more powerful conditional test [[. The above sees if $filename is matches the glob pattern *\* where the first star means "zero or more of any character" and the last two characters, \*, mean a literal star character. Thus, the above tests for whether filename ends with a literal *. Another solution to this problem using [[ can be found in @broslow's answer.