Proper implementation of an inter process communication (IPC)

Is the following a proper implementation of an inter-process communication?

#include <stdio.h>
#include <fcntl.h>
#include <sys/poll.h>

int main(int argc, char** argv) {
    if (argc > 1) {
//Sending side
        struct stat buffer;
        if (stat("/tmp/PROCAtoPROCB", &buffer) != 0)
            mkfifo("/tmp/PROCAtoPROCB", (mode_t)0600);

        int fdFIFO = open("/tmp/PROCAtoPROCB", O_WRONLY | O_NONBLOCK);
        if (fdFIFO > 0) {
            write(fdFIFO, (void *)argv[1], sizeof(argv[1]));
            close(fdFIFO);
        }
    } else {
//Receiving side
        int fdFIFO = -1;
        struct stat buffer;
        if (stat("/tmp/PROCAtoPROCB", &buffer) != 0)
            mkfifo("/tmp/PROCAtoPROCB", (mode_t)0600);

        while (1) {
            struct pollfd pollfds[1];
            if (fdFIFO == -1)
                fdFIFO = open("/tmp/PROCAtoPROCB", O_RDONLY | O_NONBLOCK);
            pollfds[0].fd = fdFIFO;
            pollfds[0].events = POLLIN;
            poll(pollfds, 1, -1);
            if (pollfds[0].revents & POLLIN) {
                char buf[1024];
                read(fdFIFO, &buf, 1024);
                close(fdFIFO);
                fdFIFO = -1;
                printf("Other process says %sn", buf);
            }
            printf("End of loopn");
        }
    }
    return 0;
}

It seems to be working but I’m wondering if there could be a race condition leading to hanging. One constraint is that both processes need to be started independently and in any order.

Answer

Some stress tests showed no problem so the implementation seems OK if somebody wants to reuse the code.

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Answer