renaming files

renaming files with regex

renaming

Maybe if I write this down I will actually remember next time

shell expansion

quick:

${var#pattern} shortest prefix pattern trim, ## for longest
${var%pattern} shortest suffix pattern trim, %% for longest
${var/pattern/repl} replace 1st pattern with repl
${var//pattern/repl} replace all pattern with repl

1for f in *.txt; do
2  mv $f "${f%txt}md"
3done
4
5# or with find for more precise targeting
6find . -name '*.txt' -exec sh -c 'f={}; mv $f ${f%txt}md'

zmv

a zsh module in other functions

uses globbing (instead of regex)
() to capture for reference with $n (a variable where parameter expansion can be applied)
$f for filename

1zmv '(*).txt' '$1.md'

rename

the one that comes with util-linux on Arch, takes a pattern and what to replace it with and some files, super undocumented

1rename md txt *

perl-rename

basically sed for file names

1perl-rename 's/(.*).md/\1.txt/' *