Can not open FIFO for any operations

Asked Apr 13 '20 at 07:20

Active Apr 13 '20 at 07:34

Viewed 65 times

I write the program and create FIFO. It was created, but I can not open it for any operations. I saw similar questions here can not open FIFO , but actually I didn't understand its answer, but I think I've got something with permissions too. Can somebody please explain what is going on?

if (mkfifo("myFifo", 777) == -1) {
    fprintf(stderr, "Impossible");    
    _exit(0);
}
int fifo;
fifo = open("myFifo", 777);

edited Apr 13 '20 at 07:34

asked Apr 13 '20 at 07:20

IWProgrammer

What is `str`? Please always provide [mcve]. – Jean-Baptiste Yunès Apr 13 '20 at 07:22
1

Also read `open` manual, second argument should be something like `O_RDONLY`, etc... – Jean-Baptiste Yunès Apr 13 '20 at 07:23
777 is not equal to -1, so the equivalent is `mkfifo("myFifo", 0)`. Check your parentheses. – user3386109 Apr 13 '20 at 07:25
@Jean-BaptisteYunès sorry, edited justn now – IWProgrammer Apr 13 '20 at 07:37
1

777 should be 0777. – user3386109 Apr 13 '20 at 07:37
1

The mkfifo mode should more likely be 0664. You usually don't want it executable or world-writable. – Jens Apr 13 '20 at 07:39
`open("myFifo",O_RDONLY)`... – Jean-Baptiste Yunès Apr 13 '20 at 07:40
1

Note that `777 != 0777`. The former is 01411 (octal), which is `r----x--t`, which probably is not what you want. Also: The second argument to `open()` is NOT the create mode, but `flags`. – dhke Apr 13 '20 at 07:40

Can not open FIFO for any operations

0 Answers0