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pipe(2) [opensolaris man page]

pipe(2) 							   System Calls 							   pipe(2)

NAME
pipe - create an interprocess channel SYNOPSIS
#include <unistd.h> int pipe(int fildes[2]); DESCRIPTION
The pipe() function creates an I/O mechanism called a pipe and returns two file descriptors, fildes[0] and fildes[1]. The files associated with fildes[0] and fildes[1] are streams and are both opened for reading and writing. The O_NDELAY, O_NONBLOCK, and FD_CLOEXEC flags are cleared on both file descriptors. The fcntl(2) function can be used to set these flags. A read from fildes[0] accesses the data written to fildes[1] on a first-in-first-out (FIFO) basis and a read from fildes[1] accesses the data written to fildes[0] also on a FIFO basis. Upon successful completion pipe() marks for update the st_atime, st_ctime, and st_mtime fields of the pipe. RETURN VALUES
Upon successful completion, 0 is returned. Otherwise, -1 is returned and errno is set to indicate the error. ERRORS
The pipe() function will fail if: EMFILE More than {OPEN_MAX} file descriptors are already in use by this process. ENFILE The number of simultaneously open files in the system would exceed a system-imposed limit. ATTRIBUTES
See attributes(5) for descriptions of the following attributes: +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |Interface Stability |Standard | +-----------------------------+-----------------------------+ |MT-Level |Async-Signal-Safe | +-----------------------------+-----------------------------+ SEE ALSO
sh(1), fcntl(2), fstat(2), getmsg(2), poll(2), putmsg(2), read(2), write(2), attributes(5), standards(5), streamio(7I) NOTES
Since a pipe is bi-directional, there are two separate flows of data. Therefore, the size (st_size) returned by a call to fstat(2) with argument fildes[0] or fildes[1] is the number of bytes available for reading from fildes[0] or fildes[1] respectively. Previously, the size (st_size) returned by a call to fstat() with argument fildes[1] (the write-end) was the number of bytes available for reading from fildes[0] (the read-end). SunOS 5.11 23 Apr 2002 pipe(2)

Check Out this Related Man Page

dup2(3C)						   Standard C Library Functions 						  dup2(3C)

NAME
dup2 - duplicate an open file descriptor SYNOPSIS
#include <unistd.h> int dup2(int fildes, int fildes2); DESCRIPTION
The dup2() function causes the file descriptor fildes2 to refer to the same file as fildes. The fildes argument is a file descriptor refer- ring to an open file, and fildes2 is a non-negative integer less than the current value for the maximum number of open file descriptors allowed the calling process. See getrlimit(2). If fildes2 already refers to an open file, not fildes, it is closed first. If fildes2 refers to fildes, or if fildes is not a valid open file descriptor, fildes2 will not be closed first. The dup2() function is equivalent to fcntl(fildes, F_DUP2FD, fildes2). RETURN VALUES
Upon successful completion a non-negative integer representing the file descriptor is returned. Otherwise, -1 is returned and errno is set to indicate the error. ERRORS
The dup2() function will fail if: EBADF The fildes argument is not a valid open file descriptor. EBADF The fildes2 argument is negative or is not less than the current resource limit returned by getrlimit(RLIMIT_NOFILE, ...). EINTR A signal was caught during the dup2() call. EMFILE The process has too many open files. See fcntl(2). ATTRIBUTES
See attributes(5) for descriptions of the following attributes: +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |Interface Stability |Standard | +-----------------------------+-----------------------------+ |MT-Level |Async-Signal-Safe | +-----------------------------+-----------------------------+ SEE ALSO
close(2), creat(2), exec(2), fcntl(2), getrlimit(2), open(2), pipe(2), attributes(5), standards(5) SunOS 5.11 19 Dec 2003 dup2(3C)

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