Pipe

Pipe Manager (QNX)

Syntax:

Pipe &

Options:

None.

Description:

Pipe implements the subset of file I/O known as pipes (or anonymous FIFOs). A simple form of interprocess communication, pipes are mostly used to connect the output of one process to the input of another to form a series of filters.

Although Fsys also implements pipes, Pipe doesn't need a disk to act as the pipe buffer, as it does all its buffering in memory. Hence you can use Pipe on diskless workstations. Also, since it's optimized for pipe I/O -- that's all it does -- Pipe often achieves better pipe throughput than Fsys. When a machine is running Fsys it is possible and normally desirable to also run Pipe. When this is done, all pipes will go through Pipe.

You must be root to run Pipe.

Examples:

Start the pipe manager:

    Pipe &

Files:

The Pipe manager closes its standard input, standard output and standard error immediately after its startup initializations have been completed. Any errors that occur during startup will result in error messages being written to standard error.

Exit status:

Pipe terminates only if an error occurs during startup or if it has been started in the foreground and has forked a copy of itself as a background process.

0

Pipe has successfully forked a copy of itself in the background.

>0

An error occurred during initialization. A diagnostic message will have been written to standard error.

See also:

Fsys