dup2

Syntax

#include <unistd.h> int dup2(int existing_handle, int new_handle);

Description

This call causes new_handle to refer to the same file and file pointer as existing_handle. If new_handle is an open file, it is closed.

Return Value

The new handle, or -1 on error.

Portability

ANSI/ISO C	No
POSIX	1003.2-1992; 1003.1-2001

Example

/* copy new file to stdin stream */ close(0); dup2(new_stdin, 0); close(new_stdin);