parallel processing PDF files using a specified number of paralellized processes.

Pdf_processor.sh

tmp=`mktemp`;
[[ $2 ]] && {
    while read filename; do pdf2txt "${filename}" -o  "${filename}.txt"; done <"$2"
} || {
    find . -name "*pdf" -print > $tmp;
    nlineas=$(( $(wc -l < $tmp) / $1 ))

    for i in $(seq 0 $nlineas); do
        [[ $i == $nlineas ]] && {
            tail -n+$(( $i * $1 )) $tmp > ${tmp}_${i}
        } || {
            tail -n+$(($i * $nlineas)) ${tmp}|head -n$((($i*$nlineas) +  $nlineas)) > ${tmp}_${i}
        }
        echo ${tmp}_${i} | parallel --gnu "bash $0 $1 {}" &
    done
}