Minimalist git multi script. Make alias 'gm' to script, use as "gm <git_command>" to run command across multiple checked out git repos.

git_multi.sh

#!/bin/bash
set -e

ARG="$1"
WORK_DIR=$(pwd)

run() {
  for DIR in $(find $WORK_DIR/ -maxdepth 1 -type d)
  do
    cd "${DIR}"
    [[ -d .git ]] && printf "\n\n==== %s ====\n\n" $(basename ${DIR}) && git $ARG
  done
  
  #Return to work directory
  cd $WORK_DIR
}

run