>On 29/06/2016 18:06, Stanisław Wawszczak wrote: >> Dear Corinna, >> >> I am sorry about confusing you. >> Simply: >> >> ----------------------------- Issue >> ------------------------------------ >> Call to ftok() returns negative value > > Hi Stanisław, > > may be I am missing somthing, but nothing on > http://pubs.opengroup.org/onlinepubs/9699919799/functions/ftok.html > > suggest me that the return value must be positive
Hi Marco, You are absolutely right. But all code examples, what I have seen including sblim-sfcbd (what I have to compile) is testing result from ftok() as positive value. The case-test code is working on native linux with positive value returned from ftok(). I have made some tests and I have stated that making call to getsem() on Cygwin with nsems == 1 is working with negative key returned from ftok. So this is not my case at all. I am really sorry about wrong question. *Real question is why Cygwin's implementation of getsem() is not allowing to ask for more than nsems == 1?* Here is stated, that the platform is limiting the nsems value: http://pubs.opengroup.org/onlinepubs/9699919799/functions/semget.html#tag_16_512 This code is not working, return errno == 22 (EINVAL, I guess...) #include <sys/ipc.h> #include <sys/sem.h> #include <stdio.h> #include <errno.h> int main(int argc, char**argv) { int provs = 100; key_t semHandle = ftok("/etc/fstab", 'A'); int sfcbSem = -1; printf("semHandle <= 0 ; (semHandle = %lld)\n", semHandle); if ((sfcbSem = semget(semHandle, 2, IPC_CREAT | IPC_EXCL | 0600)) == -1) { printf("error semget, errno = %d\n", errno); } printf("finished\n"); return 0; } > Regards > Marco -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
