How to check the first character in a string in Bash or UNIX shell?

Question

I\'m writing a script in UNIX where I have to check whether the first character in a string is \"/\" and if it is, branch.

For example I have a string:

/         


        

Answer 1

$ foo="/some/directory/file"
$ [ ${foo:0:1} == "/" ] && echo 1 || echo 0
1
$ foo="server@10.200.200.20:/some/directory/file"
$ [ ${foo:0:1} == "/" ] && echo 1 || echo 0
0