Category Archives: Programming

Material related to computer programming.

Postfix Virtual Mailboxes and Procmail Filtering

Posted on by
Reply

Am interested in getting procmail to work with my Postfix/Courier setup. Am using virtual domains/aliases/mailboxes stored in a MySQL database and a Maildir file system. Have only just begun my investigations. So far I’ve found:

Security considerations for find

Posted on by
41

Read about the security considerations for find. Find is a *nix tool for searching though directories for files and filtering them to build lists or run commands.

While I’m here I might as well show you my latest find command, I think it’s a beauty. :)

sudo find . \
  \( \( \( \! -user jj5 \) -or \( \! -group jj5 \) \) \
    -execdir chown jj5:jj5 '{}' \+ \) , \
  \( \( -type d \( \! -perm -u+rwx \) \) \
    -execdir chmod u+rwx '{}' \+ \) , \
  \( \( -type f \( \! -perm -u+rw \) \) \
    -execdir chmod u+rw '{}' \+ \)

Bash wait

Posted on by
27

Today I learned about the ‘wait’ command. It waits for background processes to terminate before returning, so you can fire off a bunch of jobs to be run in parallel and then wait for all of them to complete before continuing, like in this take-ownership.sh script I wrote tonight:

#!/bin/bash
if [ -n "$1" ]; then
  pushd "$1" > /dev/null 2>&1
  if [ "$?" -ne "0" ]; then
    echo "Cannot change dir to '$1'.";
    exit 1;
  fi
fi
sudo chown -R jj5:jj5 . &
sudo find . -type d -exec chmod u+rwx {} \; &
sudo find . -type f -exec chmod u+rw {} \; &
if [ -n "$1" ]; then
  popd > /dev/null 2>&1
fi
wait
exit 0