(All tags.)
time command, TIMEFMT, and REPORTTIMEtime is a POSIX utility for timing commands. Most shells build it in, and Zsh’s version has a lot more to offer than the one in Bash.
(#i) glob flag and the no_case_glob optionBy default, Zsh globs are case-sensitive, so *.jpg matches beach.jpg but not CAT.JPG or dog.Jpg:
(D)By default, Zsh globs skip hidden files and directories, meaning those with names starting with a dot. For example, in a project directory, * misses all the configuration files and directories:
zparseoptsSometimes you want your shell scripts to take options, like --verbose or --help, along with any positional arguments. Handling options is fiddly to do by hand, with the traditional portable approach being a large block of code using a while loop, a case statement, and some shifts. Bash has the getopts builtin, but it only handles single-letter options, like -v. Zsh also has getopts, for compatibility, with the same limitation.
push-lineDo you ever do this? You carefully type out a command, like this pytest one:
I’ve written a few posts on Zsh’s glob qualifiers recently, covering:
(n) glob qualifierGlobs sort filenames character by character, so numbered files often come out in a surprising order, with 10 before 2. Zsh has a neat fix for this: the n glob qualifier, which applies a “natural” sort, treating any run of digits as a number rather than a string of characters.
(OL) glob qualifierGot a directory that you want to tidy up bloat from? Whether you’re trying to find bad build artifacts in your work repository or clear out old cat videos from your home directory, Zsh’s (OL) glob qualifier can help you find the largest files.
:r (root) and :e (extension)Zsh modifiers are a family of suffixes that transform words as they’re expanded. Several of them are dedicated to slicing up filenames, replacing fiddly calls to dirname, basename, and friends. Let’s take a look at them now!
(e) or + glob qualifiersZsh glob qualifiers can select files by many built-in attributes: type, size, modification time, and more. But when no built-in qualifier fits, you can bring in the e or + qualifiers to run arbitrary code, making globs a fully programmable file filter. With great power comes great responsibility!
(m0) glob qualifiersMy downloads directory is a junk pile that I just never get around to fully clearing. So if I’ve just downloaded a bunch of files, I normally want to work with them and ignore the rest of the files.
(om[1]) glob qualifiersI’ve recently been using memray, a memory profiler for Python, to optimize the startup memory usage (and time) for a client. It’s a fantastic tool, but its flexibility hampers getting instant feedback. It takes three commands to profile a program, generate a flame graph from the profile, and open the flame graph in the browser:
Do you see this message when you open a new terminal session?