is there something totally screwed with "patch"?

[Robert P. J. Day]

  i couldn't find anything on bugzilla about this, so here goes.
after an hour of trying to figure out why a large compile of mine
wasn't working, i've narrowed it down to the "patch" command.
quite simply, "patch" doesn't.

  i've applied a short patch file against a directory of glibc
source, the command assures me that it's applying the patch, it
correctly tells me where the hunks were applied, and so on.  and
after it's all over ... no change to the file.

  as a test, i replaced my standard

  $ patch ... < patchfile

with

  $ patch ... --input=patchfile

which should be equivalent, and *now* it tells me that the 
patch file is not found!  exactly the same file that allegedly
worked when i used stdin.

  can anyone enlighten me? 

rday