Need help: mq_open returns -1 at run time

Question

#include <stdio.h>
#include <unistd.h>
#include <mqueue.h>
#include <sys/stat.h>
mqd_t mymq;
struct mq_attr msgAttr;
int main(int argc, char **argv)
int close;
msgAttr.mq_maxmsg = 100;
msgAttr.mq_msgsize = 128;
msgAttr.mq_flags = 0;
/* Creating a message queue. */
mymq = mq_open("/home/karthik/test", O_CREAT|O_RDWR,S_IRWXU, &msgAttr);
if (mymq == (mqd_t) -1)
printf("Unable to create the message = %d\n",mymq);
else
"msgSend1.c" 30 lines, 591 characters
$
$ gcc msgSend1.c -lposix4
$ ./a.out
Unable to create the message = -1

Answer 1

errno returns "interrrupted system call"
#include <stdio.h>
#include <unistd.h>
#include <mqueue.h>
#include <sys/stat.h>
#include <string.h>
mqd_t mymq;
struct mq_attr msgAttr;
int main(int argc, char **argv)
int close;
int errno;
msgAttr.mq_maxmsg = 5;
msgAttr.mq_msgsize = 5;
msgAttr.mq_flags = 0;
/* Creating a message queue. */
mymq = mq_open("/home/karthik/test", O_CREAT|O_RDWR,S_IRWXU, &msgAttr);
if (mymq == (mqd_t) -1)
printf("Unable to create the message = %d errno = %d errorString = %s\n"
,mymq,errno,strerror(errno));
else
/* Release access to message queue */
close = mq_close(mymq);
"msgSend1.c" 32 lines, 672 characters
$
$ gcc msgSend1.c -lposix4
$ ./a.out
Unable to create the message = -1 errno = 4 errorString = Interrupted system cal