Single-byte I/O for keytab reads

Ken Hornstein kenh at
Thu Jun 27 17:10:00 EDT 2002

So I've noticed during some system call traces that all I/O done on
credential caches involve read()ing a byte at a time.  I did some research
on this one, and I believe I've found the culprit.

In $(src)/lib/krb5/keytab/file/ktf_util.c, I see a number of calls like

    setbuf(KTFILEP(id), NILL);

Which according to the man page makes the I/O completely unbuffered.

I assume the reason this was done was to do the "right" thing when
writing a new keytab entry, but it makes reading a lot more inefficient.
Does the use of this still make sense, even for writing a new entry?


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