Basically I can use a glob in zsh to a list. Often, it turns out, I would like to filter that list, grep’ishly I’m wondering though, if I need to do that.
Does zsh have a method to filter a list? I fear this is an obvious question, but it’s a low yield day today, mentally.
Answers:
Thank you for visiting the Q&A section on Magenaut. Please note that all the answers may not help you solve the issue immediately. So please treat them as advisements. If you found the post helpful (or not), leave a comment & I’ll get back to you as soon as possible.
Method 1
This is kind of a weird question, seeing as zsh is the only shell with this feature. It’s called glob qualifiers. The manual is, as usual, rather terse and devoid of examples. The Zsh-lovers page has a few examples. Googling zsh "glob qualifiers" turns up a few blog posts and tutorials. You can also search for "glob qualifier" on this site.
The basics: glob qualifiers are in parentheses at the end of the glob. The most useful ones are the punctuation signs to select only certain file types.
echo *(/) # directories echo *(.) # regular files echo *(@) # symbolic links echo *(-/) # directories and symbolic links to directories
There are other qualifiers to filter on metadata such as size, date and ownership.
# files owned by the user running zsh, over 1MB, last modified more than 7 days ago echo *(ULm+1m+7)
Glob qualifiers can also control the order of matches, and restrict the number of matches.
echo *(Om[1,10]) # The 10 oldest files
You can set up arbitrary filters by calling a function, with the + qualifier (you can even put the code inline with the e qualifier, if you don’t mind the tricky quoting).
Note that unfortunately all of this only works on globs. If you want to build a list of file names this way, you need to filter when you’re globbing. If you want to filter a list that you’ve already built, there’s a completely different syntax, parameter expansion flags, which can only perform simple text filtering ("${(@)ARRAY:#PATTERN}").
All methods was sourced from stackoverflow.com or stackexchange.com, is licensed under cc by-sa 2.5, cc by-sa 3.0 and cc by-sa 4.0