.pa 1 .he 'PIPE (II)'1/15/73'PIPE (II)' .ti 0 NAME pipe -- create a pipe .sp .ti 0 SYNOPSIS sys pipe / pipe = 42.; not in assembler .br (file descriptor in r0) .sp .ti 0 DESCRIPTION The pipe____ system call creates an I/O mechanism called a pipe. The file descriptor returned can be used in both read and write operations. When the pipe is written, the data is buffered up to 504 bytes at which time the writing process is suspended. A read on the pipe will pick up the buffered data. .sp It is assumed that after the pipe____ has been set up, two (or more) cooperating processes (created by subsequent fork____ calls) will pass data through the pipe with read____ and write_____ calls. The shell has a syntax to set up a linear array of processes connected by pipes. .sp Read calls on an empty pipe (no buffered data) with only one end (no synonymous file descriptors resulting from fork____ or dup___) return an end-of-file. Write calls under similar conditions are ignored. .ti 0 SEE ALSO sh(I), read(II), write(II), fork(II) .sp .ti 0 DIAGNOSTICS The error bit (c-bit) is set if 10 files are already open. .sp .ti 0 BUGS --