HANDY SHELL COMMANDS: (more to be added)

Make filenames lower case:
for i in * ; do mv $i `echo $i |tr '[A-Z]' '[a-z]'` ; done

Generate afm files for pfb fonts:
for i in *.pfb ; do pfb2pfa $i >`basename $i .pfb`.pfa ; pfa2afm `basename $i .pfb`.pfa >`basename $i .pfb`.afm ; done

Convert pfm files to afm files:
for i in *.pfm ; do pfm2afm $i ; done

Rasterise Postscript at 100 DPI:
zcat foo.ps.gz |
gs -q -dNOPAUSE -sDEVICE=pbm -r100x100 -sOutputFile=- - |ppmtogif

Correct file name numbering:
find . -maxdepth 1 -name '000-???.tif' -exec sh -c 'mv "{}" `echo "{}"
|sed -e "s/\(000-\)\(...\.tif\)/\2/"`' \;

Correct line ends in files from MS-DOS on all files in current dir,
placing results in ./b (which must exist):
find -maxdepth 1 -name '*.txt' -exec sh -c "sed -e 's/'`echo -ne '\r'`'/'`echo -ne '\n'`'/g' < \"{}\" > b/\"`basename {}`\"" \;

Rotate TIFF images by 90 degrees, placing results in b/ (which must exist):
find -maxdepth 1 -name '*.tif' -exec sh -c "tifftopnm \"{}\" |pnmflip
-rotate90 |pnmtotiff > b/\"`basename {}`\"" \;

Scale JPEG's by 50%, put result in b/:
find -maxdepth 1 -name '*.jpeg' -exec sh -c "echo \"{}\" ; cat \"{}\"
|djpeg -scale 1/2 |cjpeg -quality 90 >b/\"`basename {}`\"" \;

Try to extract a list of C function definitions from a file
(to find prototypes, remove the ^ near the end of the expression):
grep -e '^[[:alnum:]][^()=]* [^()= ][^=]*(.*)[^;]'

The following are more for my reference and not of so much use to anyone
else...

Take a targa file, add copyright notice and convert to jpeg;
change c.pbm to c2.pbm for white, edit yoff to 30 pixels above bottom of
image:
tgatoppm foo.tga |pnmcomp -alpha ~/c2.pbm -yoff 730 ~/c.pbm |cjpeg >foo.jpeg

Print a gif bitmap on 300 DPI HP laserjet:
giftopnm foo.gif pbmtolj -resolution 300 |lpr

Print a gif bitmap on 300 DPI HP laserjet in landscape mode:
giftopnm foo.gif |pnmflip -ccw |pbmtolj -resolution 300 |lpr

Reduce A4 bitmap to fit on letter paper and pad to centre:
pnmscale 0.931 |pgmtopbm -threshold |pnmpad -white -l84

Convert PDF files to TIFF, placing result in output dir:
find . -name '*.pdf' -exec sh -c 'echo Processing "{}" ; mkdir "`dirname
"{}"`/output" 2>/dev/null ; gs -dNOPAUSE -sDEVICE=tiffpack -r600x600
-sOutputFile="`dirname "{}"`/output/`basename "{}" ".pdf"`-%d.tif" "{}" -c
quit' \; |tee output.txt

Generate postscript file in signature (2x A5 pages to A4):
cat _a.ps |psbook |psnup -pa4 -s1 -2 >pa.ps

Print odd pages:
psselect -o pa.ps >pa_o.ps

Print even pages:
psselect -e pa.ps >pa_e.ps

Print A5 booklet on A4 duplex on HP5Si:
cat book.ps |psbook |psnup -pa4 -s1 -2 |\
lpr -Plp2o -J 'PageSize:A4 Duplex:DuplexTumble'

Print A4 booklet on A3 duplex on HP5Si:
cat book.ps |psbook |psnup -pa3 -s1 -2 |\
lpr -Plp2o -J 'PageSize:A3 Duplex:DuplexTumble'