UPDATE: 12/25/2006 – With the new site design and the lack of usage of the links, I decided to take them off. No complaints thus far! This modification still works if you would like to use it.
I was the butt of some joking going on over at Nektros. …

Use php-Gettext. Many other projects already use it and it doesn’t require Gettext compiled in users system.
Check it out at I Hate PHP
Get it at Savannah

Documentation and examples on usage of both PHP native Gettext at Pablo Hoch blog or on the php-Gettext Class at BlogFish and why should you choose it instead PHP’s default one.

You will need to use __(‘text to translate’) when you don’t want to use it to return translation or _e(‘text to translate’) if you want to echo translation inside your code.

Then you can use my bash script (requires Linux and GNU Gettext installed in your local machine):

 
#! /bin/sh
#
# ***** BEGIN LICENSE BLOCK *****
# Version: GPL 2.0 / LGPL 2.1
#
# The Original Code is Humaneasy Consulting code.
#
# The Initial Developer of the Original Code is
# Humaneasy Consulting.
# Portions created by the Initial Developer are Copyright (C) 2006
# the Initial Developer. All Rights Reserved.
#
# Contributor(s):
#
# Alternatively, the contents of this file may be used under the terms of
# either of the GNU General Public License Version 2 or later (the "GPL"),
# or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
# in which case the provisions of the GPL or the LGPL are applicable instead
# of those above. If you wish to allow use of your version of this file only
# under the terms of either the GPL or the LGPL indicate your decision by
# deleting the provisions above and replace them with the notice and other
# provisions required by the GPL or the LGPL. If you do not delete the 
# the provisions above, a recipient may use your version of this file under
# the terms of any one of the GPL or the LGPL.
#
# ***** END LICENSE BLOCK *****
 
cmdname=`basename "

"`

MKT_DIST_TRANS=`pwd`      # `dirname "

"`

MKT_DEFAULT_NAME="./${cmdname}"

 

exitcode=0

 

#

##

## Functions

##

##########################################################################

mkt_usage()

{

echo "Usage:  ${cmdname} [option] [srcfile] [destfile]"

echo ""

echo "  options:"

echo ""

echo "    -p                   Creates the PO, POT and original MO files."

echo "    --makepo"

echo ""

echo "    -m                   Creates only the MO file."

echo "    --makemo"

echo ""

echo "  Example for PO/POT files:"

echo "    ${cmdname} -p '.php filename w/o extension' 'langcode'"

echo "       'langcode' could be, for instance, 'es' or 'pt' "

echo ""

echo "  Example for just MO"

echo "    ${cmdname} -m '.po filename'"

echo ""

echo "  -m superseeds -p. Use just one at a time."

echo "  Example for just MO"

	return 0

}

 

##########################################################################

#

OPTIONVAR=$1

if [ "${OPTIONVAR}" == "" ]; then

   mkt_usage

   exit 1

fi

 

echo ""

# MKT_DIST_TRANS="${MKT_DIST_TRANS}/wp-translations"

X=`mkdir -p "${MKT_DIST_TRANS}"/mo`

SRCFILE=$2

 

if [ "${OPTIONVAR}" == "-m" ] || [ "${OPTIONVAR}" == "-makemo" ]

then

   if [ "${SRCFILE}" == "" ]

   then

       mkt_usage

       exit 1

    fi

 

    SRCFILEPO="${MKT_DIST_TRANS}/${SRCFILE}.po"

    SRCFILEMO="${MKT_DIST_TRANS}/mo/${SRCFILE}.mo"

 

    if [ -f "${SRCFILEPO}" ]

 	then

        echo "Making ${SRCFILE} MO file for your plugin at ${MKT_DIST_TRANS}/mo' ..."

        msgfmt -o "$SRCFILEMO" "$SRCFILEPO"

        echo "The file $SRCFILEMO is ready. Can use it in your application."

     else

        echo "Source file ${SRCFILEPO} NOT found."

        echo ""

        exit 1

     fi

fi

#

 

if [ "${OPTIONVAR}" == "-p" ] || [ "${OPTIONVAR}" == "-makepot" ]

then

    LANG=$3

    if [ "${SRCFILE}" == "" ] || [ "${LANG}" == "" ]

    then

       mkt_usage

       exit 1

    fi

 

    SRCFILEPHP="${SRCFILE}.php"

    SRCFILEPOT="./wp-translations/${SRCFILE}.pot"

    SRCFILEPO="./wp-translations/${SRCFILE}-${LANG}.po"

 

    if [ -f "${SRCFILEPHP}" ]

 	then

        echo "Making $SRCFILE POT file for your Wordpress plugin/theme..."

        xgettext --keyword=__ --keyword=_e --default-domain="${SRCFILE}" \

                 --language=php "${SRCFILEPHP}" --output="${SRCFILEPOT}"

	if [ -f "${SRCFILEPOT}" ]

	   then

           cp "${SRCFILEPOT}" "${SRCFILEPO}"

           echo "${SRCFILEPO} file is ready. Can start translating."

	else

	   echo "No need to translate. Next, please ;)"

	fi

     else

        echo "Source file ${SRCFILE}.php NOT found."

        echo ""

        exit 1

     fi

fi

#

 

echo "Done. "

 

exit $exitcode

Hope it helps.