[]
, e.g. [:digit:](:digit:)
.gzip file[:digit:]*.txt
gzip file[:digit:](:digit:)*.txt
Predefined character groups are supposed to be used inside character
ranges. [:digit:]
matches one of "digt:" just like
[abc]
matches one of "abc". [:digit:](:digit:)
matches a digit.
When passing an argument to tr
which parses these by
itself without relying on globbing, you should quote it instead, e.g.
tr -d '[:digit:]'
ShellCheck is a static analysis tool for shell scripts. This page is part of its documentation.