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pipe(2) [mojave man page]

PIPE(2) 						      BSD System Calls Manual							   PIPE(2)

NAME
pipe -- create descriptor pair for interprocess communication SYNOPSIS
#include <unistd.h> int pipe(int fildes[2]); DESCRIPTION
The pipe() function creates a pipe (an object that allows unidirectional data flow) and allocates a pair of file descriptors. The first descriptor connects to the read end of the pipe; the second connects to the write end. Data written to fildes[1] appears on (i.e., can be read from) fildes[0]. This allows the output of one program to be sent to another pro- gram: the source's standard output is set up to be the write end of the pipe; the sink's standard input is set up to be the read end of the pipe. The pipe itself persists until all of its associated descriptors are closed. A pipe whose read or write end has been closed is considered widowed. Writing on such a pipe causes the writing process to receive a SIGPIPE signal. Widowing a pipe is the only way to deliver end-of-file to a reader: after the reader consumes any buffered data, reading a widowed pipe returns a zero count. The generation of the SIGPIPE signal can be suppressed using the F_SETNOSIGPIPE fcntl command. RETURN VALUES
On successful creation of the pipe, zero is returned. Otherwise, a value of -1 is returned and the variable errno set to indicate the error. ERRORS
The pipe() call will fail if: [EFAULT] The fildes buffer is in an invalid area of the process's address space. [EMFILE] Too many descriptors are active. [ENFILE] The system file table is full. SEE ALSO
sh(1), fork(2), read(2), socketpair(2), fcntl(2), write(2) HISTORY
A pipe() function call appeared in Version 6 AT&T UNIX. 4th Berkeley Distribution February 17, 2011 4th Berkeley Distribution

Check Out this Related Man Page

PIPE(2) 						      BSD System Calls Manual							   PIPE(2)

NAME
pipe -- create descriptor pair for interprocess communication SYNOPSIS
#include <unistd.h> int pipe(int fildes[2]); DESCRIPTION
The pipe() function creates a pipe (an object that allows unidirectional data flow) and allocates a pair of file descriptors. The first descriptor connects to the read end of the pipe; the second connects to the write end. Data written to fildes[1] appears on (i.e., can be read from) fildes[0]. This allows the output of one program to be sent to another pro- gram: the source's standard output is set up to be the write end of the pipe; the sink's standard input is set up to be the read end of the pipe. The pipe itself persists until all of its associated descriptors are closed. A pipe whose read or write end has been closed is considered widowed. Writing on such a pipe causes the writing process to receive a SIGPIPE signal. Widowing a pipe is the only way to deliver end-of-file to a reader: after the reader consumes any buffered data, reading a widowed pipe returns a zero count. The generation of the SIGPIPE signal can be suppressed using the F_SETNOSIGPIPE fcntl command. RETURN VALUES
On successful creation of the pipe, zero is returned. Otherwise, a value of -1 is returned and the variable errno set to indicate the error. ERRORS
The pipe() call will fail if: [EFAULT] The fildes buffer is in an invalid area of the process's address space. [EMFILE] Too many descriptors are active. [ENFILE] The system file table is full. SEE ALSO
sh(1), fork(2), read(2), socketpair(2), fcntl(2), write(2) HISTORY
A pipe() function call appeared in Version 6 AT&T UNIX. 4th Berkeley Distribution February 17, 2011 4th Berkeley Distribution
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