Write a shell script wparser.bash that would process these data files. The shell script is expected to be given the name of a directory, under which it will start the search for data files whose names...

Write a shell script
wparser.bash
that would process these data files.

The shell script is expected to be given the name of a directory, under which it will start the search for data files whose names are of the form
weather_info_*.data
as its argument. (Do not hard code the directory name in your script).
If the script is not invoked with the correct number of arguments, it should throw an usage message and terminate with a code of 1.

If the passed argument is not a valid directory name, it should throw an error message and terminate with code 1. For this particular situation (and only here), the error message must be send to the standard error and not the standard output.