makes a FIFO special file with name pathname.
mode specifies the FIFO's permissions.
It is modified by the
process's umask in the usual way: the permissions of the created
file are (mode & ~umask).
A FIFO special file is similar to a pipe, except that it is created
in a different way.
Instead of being an anonymous communications
channel, a FIFO special file is entered into the file system by
Once you have created a FIFO special file in this way, any process can
open it for reading or writing, in the same way as an ordinary file.
However, it has to be open at both ends simultaneously before you can
proceed to do any input or output operations on it.
Opening a FIFO for reading normally blocks until some
other process opens the same FIFO for writing, and vice versa.
for nonblocking handling of FIFO special files.
In the case of an error, -1 is returned (in which case, errno
is set appropriately).
One of the directories in pathname did not allow search
pathname already exists.
This includes the case where
is a symbolic link, dangling or not.
Either the total length of pathname is greater than
PATH_MAX, or an individual filename component has a length
greater than NAME_MAX.
In the GNU system, there is no imposed
limit on overall filename length, but some file systems may place
limits on the length of a component.
A directory component in pathname does not exist or is a
dangling symbolic link.
The directory or file system has no room for the new file.
A component used as a directory in pathname is not, in fact, a