bgipc_part_0500_fifos.md: mknod is used instead of mkfifo

[ZoomRmc]

I noticed that the guide promotes the use of mknod instead of mkfifo for creating the FIFOs, which contradicts the POSIX and the common advice I've seen. mkfifo isn't even mentioned as an alternative call.

Is there a specific reason, like difference in portability?

The POSIX standard states:

The mkfifo() function is preferred over this function for making FIFO special files.

The Linux manual for mknod also quotes POSIX.1-2001:

"The only portable use of mknod() is to create a FIFO-special file. If mode is not S_IFIFO or dev is not 0, the behavior of mknod() is unspecified." However, nowadays one should never use mknod() for this purpose; one should use mkfifo(3), a function especially defined for this purpose.