s/z\$prog/gz\$prog/g
s/zcat/gzcat/g
s/Zcat/Gzcat/g
s/ZCAT/GZCAT/g
s/zcmp/gzcmp/g
s/Zcmp/Gzcmp/g
s/ZCMP/GZCMP/g
s/znew/gznew/g
s/Znew/Gznew/g
s/ZNEW/GZNEW/g
s/zdiff/gzdiff/g
s/Zdiff/Gzdiff/g
s/ZDIFF/GZDIFF/g
s/zgrep/gzgrep/g
s/Zgrep/Gzgrep/g
s/ZGREP/GZGREP/g
s/zmore/gzmore/g
s/Zmore/Gzmore/g
s/ZMORE/GZMORE/g
s/zless/gzless/g
s/Zless/Gzless/g
s/ZLESS/GZLESS/g
s/zforce/gzforce/g
s/Zforce/Gzforce/g
s/ZFORCE/GZFORCE/g
s/zegrep/gzegrep/g
s/zfgrep/gzfgrep/g
s/^gzgrep /gzgrep, gzegrep, gzfgrep /