zlacker

I just performed an ad hoc file-level tree-shaking for 'src/cat.c' in GNU coreutils 8.30, starting with `gcc src/cat.c` and gradually adding arguments until I got it to build. Here's the command I ended up with.

    gcc -I. -I./lib /
      src/version.c /
      lib/progname.c /
      lib/safe-read.c /
      lib/safe-write.c /
      lib/quotearg.c /
      lib/xmalloc.c /
      lib/localcharset.c /
      lib/c-strcasecmp.c /
      lib/mbrtowc.c /
      lib/xalloc-die.c /
      lib/c-ctype.c /
      lib/hard-locale.c /
      lib/exitfail.c /
      lib/closeout.c /
      lib/close-stream.c /
      lib/fclose.c /
      lib/fflush.c /
      lib/fseeko.c /
      lib/version-etc.c /
      lib/xbinary-io.c /
      lib/version-etc-fsf.c /
      lib/binary-io.c /
      lib/fadvise.c /
      lib/full-write.c /
      src/cat.c

Those .c files add up to 5021 lines.

The .c files include 44 header files:

    lib/binary-io.h
    lib/c-ctype.h
    lib/closeout.h
    lib/close-stream.h
    lib/config.h
    lib/c-strcaseeq.h
    lib/c-strcase.h
    lib/ctype.h
    lib/error.h
    lib/exitfail.h
    lib/fadvise.h
    lib/fcntl.h
    lib/fpending.h
    lib/freading.h
    lib/full-write.h
    lib/gettext.h
    lib/hard-locale.h
    lib/ignore-value.h
    lib/limits.h
    lib/localcharset.h
    lib/locale.h
    lib/minmax.h
    lib/progname.h
    lib/quotearg.h
    lib/quote.h
    lib/safe-read.h
    lib/stdio.h
    lib/stdio-impl.h
    lib/stdlib.h
    lib/string.h
    lib/sys/ioctl.h
    lib/sys-limits.h
    lib/sys/types.h
    lib/unistd.h
    lib/unused-parameter.h
    lib/verify.h
    lib/version-etc.h
    lib/wchar.h
    lib/wctype.h
    lib/xalloc.h
    lib/xbinary-io.h
    src/die.h
    src/ioblksize.h
    src/system.h

The header files add up to 19.7k lines.

So the total line count for files GNU cat actually needs to build is at least ~25k.

(I didn't bother checking for headers including other headers.)

Next step: do this for various versions of GNU coreutils.

>>akkart+(OP)
Thanks for taking the time to do this counting, very interesting result.

>>akkart+(OP)
Much more code for much less functionality than the BSD cat which can do sockets. Not surprised at all.