Working with compressed files

Linux usually provides a couple of command piping gzip

zgrep, zcat, zdiff, zless, zmore, zegrep,...

Here is a simple extension of tail and head for zipped files, that you can call ztail and zhead (example is for tail, replace "tail" with "head" everywhere to get zhead) and add to your own /bin directory:

Caution:

very basic version, works when the options starts with '-' so it works with '-n10' but fails with '-n 10'. Should be easily improved...

<source lang="bash">

1. !/bin/bash

1. based on zless

PATH=${GZIP_BINDIR-'/bin'}:$PATH

version="ztail 0.1"

usage="Usage: $0 [OPTIONS]... [FILES]...

Same as the 'tail' command, but operate on the uncompressed contents of any compressed FILEs. Options are the same as for 'tail'."

case $1 in --help) exec echo "$usage";; -h) exec echo "$usage";; --version) exec echo "$version";; esac

options="" count=0 for i in $@; do str="$i" if test -f $i && [ ${str:(-3)} = ".gz" ]; then

   files[++count]=$str

else

   if [ ${str:0:1} = "-" ] && [ $str != "-v" ] && [ $str != "--verbose" ]; then

options=$options"$i "

   elif [ $str != "-v" ] && [ $str != "--verbose" ]; then
       echo -ne "***Warning: $i is neither a regular zip file or a regular option***\n\n"
   fi

fi done

if [ $count -gt 0 ]; then

   if [ $count -eq 1 ]; then
       exec gzip -cd ${files[1]} | tail $options
   else
       for j in `seq 1 $count`; do
           echo "==>"${files[j]}"<=="
           exec gzip -cd ${files[j]} | tail $options
       done
   fi

else

   echo -ne "***Warning: no regular zip files given***\n\n"
   exec echo "$usage"

fi </source>