Guest uploader setup script

Just slammed together a script to add users and give them access to the "upload" user directory.

Edit: Sorry for the updates, it turned out the first version was not optimal.

#!/bin/sh

# Usage: uploader [username ...]

error()
{
    test -t 1 && {
        tput setf 4
        echo "$1" >&2
        tput setf 7
    } || echo "$1" >&2
    exit 1
}

users="upload $*"

for user in $users
do
    # Create user if necessary
    id $user 1>/dev/null 2>&1
    if [ "$?" -ne "0" ]
    then
        useradd --groups upload --comment "Upload user" $user && \
        echo "Created upload user '${user}'." || \
        error "Could not create upload user '${user}'."
    fi
done

# Disable upload password
usermod --lock upload

# Files
chown -R upload:upload ~upload || \
error "Could not change owner of upload home dir"
chmod -R ug+rwX,o= ~upload || \
error "Could not change rights of upload home dir"