.TH SYS-PIPE 2.SH NAMEpipe \- create an interprocess channel.SH SYNOPSIS.EXinclude "sys.m";sys := load Sys Sys->PATH; pipe: fn(fds: array of ref FD): int;.EE.SH DESCRIPTION.B Pipecreates a buffered channel for interprocess I/O via file descriptors.It allocates a pipe from the pipe device and returns in the array.B fdsfile descriptors for the two pipe ends. Both returned file descriptors are opened for both reading and writing.RB ( Sys->ORDWR ).Data written on one file descriptor can be read from the other.The details of flow control and buffering are given in.IR pipe (3).When no references remain to the file descriptor representingone end of a pipe, and all remaining data has been read at the other end,subsequent reads at that end will return 0 bytes.Writes to a pipe with no reader produce an exception..PPThe array.B fdspassed to the system call must have a length of at least 2;only entries 0 and 1 are updated..PPLimbo applications typically use typed Limbo channels, not pipes, for efficientcommunication by cooperating processes.Pipes are still useful, however,to connect applications that do not (or cannot) share such channels,or when a system interface requires a file descriptor.For instance, a process that serves the Styx protocol canpass the file descriptor for one end of a pipe to.B Sys->mount(see.IR sys-bind (2)),and read and write Styx messages on the other end of the pipe..SH DIAGNOSTICSReturns 0 on success; -1 on failure..SH "SEE ALSO".IR pipe (3)