You can tell this is not "serious shell" by just this part: 1 #!/bin/sh ... 6 local arg arg_safe `local' is a bashism. You should not entrust te

You can tell this is not "serious shell" by just this part: 1 #!/bin/sh ... 6 local arg arg_safe `local' is a bashism. You should not entrust teaching shell programming to somebody who can't tell the difference between #!/bin/sh and #!/bin/bash.