select() and named pipes

[Enrico Forestieri]

I am experiencing a problem with select() and named pipes in cygwin 1.7.
The attached test case segfaults on the select() call, but works fine
with both cygwin 1.5 and linux.

-- 
Enrico

#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <sys/select.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>

#define FIFONAME "/tmp/pipe"

int main(void)
{
    int fd;
    int nsel;
    fd_set readfds;
    FD_ZERO(&readfds);

    if (mkfifo(FIFONAME, 0600) < 0) {
        perror("mkfifo");
        exit(1);
    }

    fd = open(FIFONAME, O_RDONLY | O_NONBLOCK);

    if (fd < 0) {
        perror("open");
        remove(FIFONAME);
        exit(2);
    }

    FD_SET(fd, &readfds);
    do {
        nsel = select(fd + 1, &readfds, 0, 0, 0);
    } while (nsel == -1 && (errno == EINTR || errno == EAGAIN));

    if (nsel == -1) {
        perror("select");
        exit(3);
    }

    if (FD_ISSET(fd, &readfds)) {
        char buf[100];
        int status;
        while ((status = read(fd, buf, sizeof(buf) - 1))) {
            if (status > 0) {
                buf[status] = '\0';
                printf("%s", buf);
            } else {
                printf("\n");
                if (errno != EAGAIN)
                    perror("read");
                break;
            }
        }
    }

    close(fd);
    remove(FIFONAME);
    return 0;
}


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