i don't find this line in the php-3.x series,
although socket communication is not possible
in irix: fgets() never returns as long as
the other side keeps the socket open and
php is blocked by waiting for data.
The above error can trivially fixed by writing:
int ii;
if ((ii = FP_FGETC(socketd, (FILE*)what, issock)) == EOF) {
  *buf = ii;
  ...
} else {
  *buf = ii;
  ...
}

my last explanation is a bit unclear, sorry!
with all php-3.0.x versions, i have the
following problem with socket usage and php:
When the socket connection is established,
i.e. between the php-Script(client) and a
mail server, the php script could _only_
receive
data, when the data written by the server
are already received by the client OS protocol
stack. Otherwise, i.e. when the client
tries to read (blocking or unblocking) data,
the fgets() function _never returns data.
Even if the data packets from the server
side of the socket arrives one second later,
fgets() never return any byte more.
Using blocking reads: the function fgets()
returns never.
Using unblocking reads: the function fgets()
never returns any byte.

Perhaps the handling of EOF in fgets()
is a problem. Perhaps a signed/unsigned
problem? Ok, i have to read the manual of
my debugger...

fixed in CVS