Question

What is the difference between test -L filename and test -h filename in ksh shell. From the man page, both were used to identify a symbolic link, but I want to know the exact difference.

Here is the description from the man page.

 -h file                 True if file exists and  is  a  sym-
                         bolic link.
 -L file                 True if file exists and  is  a  sym-
                         bolic link.

Answer 1

The source code for ksh93, in file bltins/test.c, shows that these two options are treated exactly the same, except for the author’s hopes for the future:

        case 'L':
        case 'h': /* undocumented, and hopefully will disappear */
            if(*arg==0 || arg[strlen(arg)-1]=='/' || lstat(arg,&statb)<0)
                    return(0);
            return(S_ISLNK(statb.st_mode));

From this I conclude that they behave exactly the same, but that -h is a legacy option and may one day disappear 🙂