PIPE(2-POSIX)       RISC/os Reference Manual        PIPE(2-POSIX)



NAME
     pipe - create an interprocess channel

SYNOPSIS
     int pipe (fildes)
     int fildes[2];

DESCRIPTION
     pipe creates an I/O mechanism called a pipe and returns two
     file descriptors, fildes[0] and fildes[1], that refer to the
     read and write ends of the pipe.  Their integer values are
     the two lowest available at the time of the function call.
     The ONONBLOCK and FDCLOEXEC flags are cleared for both
     file descriptors.

     Data can be written to file descriptor fildes[1] and read
     from file descriptor fildes[0].  A read on file descriptor
     fildes[0] accesses the data written to fildes[1] on a
     first-in-first-out (FIFO) basis.

     A process has the pipe open for reading if it has a file
     descriptor open that refers to the read end, fildes[0].  A
     process has the pipe open for writing if it has a file
     descriptor open that refers to the write end, fildes[1].

     Upon successful completion, pipe marks for update the
     st_atime, st_ctime, and st_mtime fields of the pipe.

ERRORS
     pipe will fail if:

     [EMFILE]            More than {OPEN_MAX} - 2 file descrip-
                         tors are already in use by this process.

     [ENFILE]            The system file table is full.

SEE ALSO
     read(2), write(2).
     sh(1) in the User's Reference Manual.

DIAGNOSTICS
     Upon successful completion, a value of 0 is returned.  Oth-
     erwise, a value of -1 is returned and errno is set to indi-
     cate the error.











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