Generate tags files for all of the non-hidden directories under the current directory.

projtags.sh

#!/bin/sh

start=$(pwd)

for f in $(find . \( ! -regex '.*/\..*' \) -type d); do
  cd $f
  ctags *
  cd $start
done

ctags --file-scope=no -R

updatetags.sh

#!/bin/bash

start=$(pwd)

# Generate tags files in directories where "tags" is not the newest file
for f in $(find . -type f -newer ./tags); do
  cd $f
  ctags *
  cd $start
done

# Generate tags files in directories with no tags files where the parent 
# directory does have a tags file. Ignore hidden directories.
for f in $(find . -type d \( ! -regex '.*/\..*' \) \! -exec test -e '{}/tags' \; -print); do
  if [ -e ${f}/../tags ]; then
    cd $f
    ctags *
    cd $start
  fi
done