Re: [uclibc-ng-devel] uclibc(1.0.12) mq_send return value and errno issue

Hi All, Kernel version : 4.4.19-linux4sam_5.4 uclibc version : 1.0.12 uclibc threading support : NPTL Processor Arch: ARM

We create a NONBLOCKING message queue. The expected behavior is when the message queue is full, calling mq_send would return -1 and set errno to EAGAIN(11). However we are seeing some inconsistent behaviors of mq_send. When calling mq_send in a single threaded environment, the expected behavior is observed. If the program starts a second thread, which is doing completely different task, calling mq_send when the queue is full would return -11 instead of -1. Also, the errno is set to an incorrect value. Values we have seen are 0, 2, which are completely different from the expected EAGAIN(11).