Extract PostScript Font Metrics with printafm

printafm pulls an Adobe Font Metrics (AFM) file out of an installed PostScript font, something an old typesetting pipeline quietly depends on. This covers finding a usable font name, generating the file without clobbering an old one, and checking the result actually has the markers it should. The examples use printafm from Ghostscript 10.02.1, package version 10.02.1~dfsg1-0ubuntu7.9.

Allow about ten minutes. You need a shell, the ghostscript package, and an installed Type 1 PostScript font. Apart from writing the output file, this is a read-only inspection, so it normally needs no elevated privileges.

1. Check the installed command

Confirm which script will run and record the Ghostscript version. These are ordinary read-only checks:

$ command -v printafm
/usr/bin/printafm
$ dpkg-query -W -f='${Package} ${Version}\n' ghostscript
ghostscript 10.02.1~dfsg1-0ubuntu7.9
$ gs --version
10.02.1

The exact package suffix is distribution-specific; what matters for this guide is the Ghostscript release, since the local printafm(1) manpage was revised for version 10.02.1. The wrapper invokes Ghostscript in quiet, non-display mode and sends the AFM text to standard output.

2. Find a font name that Ghostscript can use

printafm takes exactly one argument, fontname. It does not take a directory and it will not pick a default font for you. Start by locating a local Type 1 font file:

$ find /usr/share/fonts -type f \( -iname '*.pfb' -o -iname '*.pfa' \) | head -n 5
/usr/share/fonts/X11/Type1/NimbusSansNarrow-Bold.pfb
/usr/share/fonts/X11/Type1/c0611bt_.pfb
/usr/share/fonts/X11/Type1/URWBookman-Light.pfb
/usr/share/fonts/X11/Type1/D050000L.pfb
/usr/share/fonts/X11/Type1/URWBookman-DemiItalic.pfb

Use the font's PostScript name for the first example, NimbusSansNarrow-Bold, rather than the .pfb pathname. Ghostscript's font lookup resolves that name on this installation. Font names are case-sensitive in practice, and the name embedded in a filename is not always the internal PostScript name, so do not guess when a lookup fails.

An empty result from that search means your machine has no Type 1 fonts in that directory: check the font package and its install locations. A TrueType or OpenType font is not automatically a valid input here just because some other program can render it.

3. Generate an AFM file without overwriting an old one

AFM output goes to standard output. Redirect it to a new pathname so the diagnostic stream stays visible in the terminal:

$ printafm NimbusSansNarrow-Bold > NimbusSansNarrow-Bold.afm
$ printf 'exit status: %s\n' "$?"
exit status: 0

$ cp --preserve=all NimbusSansNarrow-Bold.afm NimbusSansNarrow-Bold.afm.bak
$ printafm NimbusSansNarrow-Bold > NimbusSansNarrow-Bold.afm.new
$ mv NimbusSansNarrow-Bold.afm.new NimbusSansNarrow-Bold.afm

That last command only replaces the old file once generation has succeeded. If generation fails, remove the incomplete .new file and keep the original. Deleting the backup later is irreversible, so only do that once you have checked the replacement.

4. Verify the AFM structure

An AFM file is plain text. Inspect its opening records and closing marker:

$ sed -n '1,16p' NimbusSansNarrow-Bold.afm
StartFontMetrics 2.0
FontName NimbusSansNarrow-Bold
ItalicAngle 0.0
Weight Bold
Notice (URW)++,Copyright 2014 by (URW)++ Design & Development
IsFixedPitch false
Version 1.00
Copyright Copyright (URW)++,Copyright 2014 by (URW)++ Design & Development
UnderlineThickness 50
FamilyName Nimbus Sans Narrow
FullName Nimbus Sans Narrow Bold
UnderlinePosition -100
FontBBox -144 -307 1000 1094
StartCharMetrics 854
C 32 ; WX 228 ; N space ; B 228 0 228 0 ;
$ tail -n 3 NimbusSansNarrow-Bold.afm
EndCharMetrics
EndFontMetrics

Exact metadata and character count depend on the font you chose. Check the markers rather than comparing every line against this example:

$ grep -E '^(StartFontMetrics|FontName|StartCharMetrics|EndCharMetrics|EndFontMetrics)' NimbusSansNarrow-Bold.afm
StartFontMetrics 2.0
FontName NimbusSansNarrow-Bold
StartCharMetrics 854
EndCharMetrics
EndFontMetrics

If the file is empty or lacks EndFontMetrics, treat the run as failed, even if a later script happens to accept the partial file. Keep the source font installed and rerun with its correct PostScript name.

Common traps

No argument given. Running the command bare prints usage instead of picking a default font:

$ printafm
Usage: printafm fontname

Guessed font name. A wrong name produces a Ghostscript error and a non-zero status. Capture the diagnostic in a temporary file while you test:

$ printafm NOT_A_REAL_FONT > /tmp/printafm-test.afm 2> /tmp/printafm-test.err
$ status=$?
$ printf 'exit status: %s\n' "$status"
exit status: 1
$ sed -n '1,8p' /tmp/printafm-test.err

Wording can vary with the Ghostscript build; the useful evidence is a non-zero status and an error naming the unresolved font or PostScript problem. Do not reach for sudo to fix a font lookup failure: elevated privileges do not invent a font name, and running as root can leave the generated file owned by root instead of you.

Once you have finished with a temporary diagnostic, remove it if it holds nothing you need; it is not part of the AFM workflow. No service restart, font-cache rebuild or system configuration change is needed to pull metrics out of a font Ghostscript can already resolve.