git: A git extension to add a filename to the local repository's `exclude` file.

git-exclude.sh

#!/bin/sh --

# Save as "git-exclude" and set the executable flag.
# Execute as "git exclude repo_path file_path"

if [ $# -ne 2 ]; then
  echo "usage: $(basename $0 | sed 's/-/ /g') <repo-dir> <file-path>" > /dev/stderr
  exit $(false)
fi

fullfilepath="${1}/${2}" 
if [ ! -f "${fullfilepath}" ]; then
  echo "File \"${2}\" not found in repo \"${1}\"." > /dev/stderr
  exit $(false)
fi

echo "${2}" >> "${1}/.git/info/exclude"