Greetings, Lavrentiev, Anton (NIH/NLM/NCBI) [C]! > There's some inconsistency between <sys/select.h> and <sys/param.h>:
> sys/select.h has this: > ----------------------- > /* > * Select uses bit masks of file descriptors in longs. > * These macros manipulate such bit fields (the filesystem macros use chars). > * FD_SETSIZE may be defined by the user, but the default here > * should be >= NOFILE (param.h). > */ > #ifndef FD_SETSIZE > #define FD_SETSIZE 64 > #endif > ---------------------- > Now, this is the relevant part of sys/param.h looks like this: > ---------------------- > /* Max number of open files. The Posix version is OPEN_MAX. */ > /* Number of fds is virtually unlimited in cygwin, but we must provide > some reasonable value for Posix conformance */ > #define NOFILE 8192 > ---------------------- > So it's either "<= NOFILE" that was actually meant to be there in the comment > (or, > an equivalent "should NOT be > NOFILE"), or FD_SETSIZE should have been > defined as 8192, > if the comment is actually correct. Or maybe I'm missing something here :-) > I understand that if I redefined FD_SETSIZE in my code before including > <sys/select.h>, > it'd work with whatever large (or small) fd_set I need, but that's not what > I'm after. I'm no expert, but it seems the FD_SETSIZE should have been 128. Long is 8 bytes, 64 bits. One bit if one open file, 64 * 64 = 4096. -- With best regards, Andrey Repin Tuesday, July 5, 2022 17:52:26 Sorry for my terrible english... -- Problem reports: https://cygwin.com/problems.html FAQ: https://cygwin.com/faq/ Documentation: https://cygwin.com/docs.html Unsubscribe info: https://cygwin.com/ml/#unsubscribe-simple