Combining pdf with linux via the command-line

I’ve always found a need for this, and with some digging, I’ve found a couple of ways to do this. The simplist is with ImageMagik, but I’ve found the default values leave the quality a little lacking. However, I’ve found an article that uses GhostScript to do it, and it does a wonderful job.

gs -dBATCH -dNOPAUSE -q -sDEVICE=pdfwrite -sOutputFile=output.pdf input1.pdf input2.pdf

They suggest putting it in an alias, but I’ve gone a step further and just put it in a bash script in ~/bin/combinepdf

#!/bin/bash

if [ $# -le 1 ]
then
     echo "usage: combinepdf output.pdf input1.pdf ... inputN.pdf"
exit -1
fi

OUTPUT=$1

if [ -e $OUTPUT ]
then
     echo "Output file \"$OUTPUT\" exists"
exit -1
fi

fnum=2

INPUT="$2"
ARGV=( $@ )

while [ $fnum -lt $# ]
do
     INPUT=`echo $INPUT" "${ARGV[$fnum]}`
     let "fnum += 1"
done

gs -dBATCH -dNOPAUSE -q -sDEVICE=pdfwrite -sOutputFile=$OUTPUT $INPUT

Then chmod a+x ~/bin/combinepdf and then run it.