[uClibc]fseek(3) idempotency

[Matt Kraai]

On Tue, Sep 25, 2001 at 08:35:37AM -0600, Manuel Novoa III wrote:
> A couple of notes:
> 
> 1) I agree that there is no need in this case to invalidate the
>    readahead buffer.  Regarding Matt's patch though, the
>    "if (READING(fp))" test is unnecessary.  The assignment works
>    for both reading or writing (although redundant here).

OK, then I'll commit the appropriately modified patch.  I'm an
infrequent uClibc hacker, so I plead ignorance.

> 2) Even with this change, seek_sub_file() is still broken as fseek()
>    will set the error flag for the FILE if it corresponds to a pipe
>    or fifo, and subsequent reads should fail.  A clearerr() call
>    needs to be done too.

Then fseek() isn't SUSv2 compliant:

	... otherwise they return -1 and set errno to indicate the
	error.

Contrast this with the description for fread():

	Otherwise, if a read error occurs, the error indicator for
	the stream is set and errno is set to indicate the error. 

OK to also commit a patch which prevents fseek() from setting the
error indicator?

Matt