2
votes
2answers
103 views

How do I check that a filename conforms to a pattern?

I'm tasked with writing a shell script which checks that a filename conforms to a specific pattern and I'm not sure how to go about it. The filename should follow a pattern which looks like: ...
5
votes
2answers
2k views

Pattern Matching Exclude Duplicate Characters

Is there a regular expression for the following that matches characters in a character set but only once? In other words, once a character is found, remove it from the set. If grep cannot do this, ...