PIPE(2) PIPE(2)
NAME
pipe - create an interprocess channel
SYNOPSIS
int pipe(fildes)
int fildes[2];
DESCRIPTION
Pipe creates a buffered channel for interprocess I/O commu-
nication. Two file descriptors returned in fildes are the
ends of pair of cross-connected streams; see stream(4). Data
written via fildes[1] is available for reading via fildes[0]
and vice versa.
After the pipe has been set up, cooperating processes cre-
ated by subsequent fork(2) calls may pass data through the
pipe with read and write calls. The bytes placed on a pipe
by one write are contiguous even if many process are writ-
ing. Writes induce a record structure: a read will not
return bytes from more than one write; see read(2).
Write calls on a one-ended pipe raise signal SIGPIPE. Read
calls on a one-ended pipe with no data in it return an end-
of-file for the first several attempts, then raise SIGPIPE,
and eventually SIGKILL.
SEE ALSO
sh(1), fork(2), read(2), select(2), stream(4)
DIAGNOSTICS
EIO, EMFILE, ENFILE, ENXIO
BUGS
Buffering in pipes connecting multiple processes may cause
deadlocks.
Some line discipline modules discard the record delimiters
inserted by write.
On many other versions of the system, only fildes[0] may be
read and only fildes[1] may be written.