pipe

Description

The pipe() function creates a pipe and places two file descriptors, one each into the arguments fildes[0] and fildes[1]. These arguments refer to the open file descriptions for the read and write ends of the pipe. Their integer values are the two lowest available at the time of the pipe() function call. The O_NONBLOCK and FD_CLOEXEC flags are clear on both file descriptors. The fcntl() function can be used to set these flags.

Data is 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 file descriptor fildes[1] on a first-in-first-out basis.

A process has the pipe open for reading if the read end file descriptor, fildes[0], is open. A process has the pipe open for writing if the write end file descriptor, fildes[1] is open.

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

Implementation Considerations

None.

Errors

If an error occurs, errno is set to one of the following values:

See Also

fcntl(), open(), read(), write(), POSIX.1