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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 referring
       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  descrip-
		       tor.

       EBADF	       The files2 argument is negative or is not less than the
		       current	  resource    limit    returned	   by	 getr-
		       limit(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),
       lockf(3C), attributes(5), standards(5)

SunOS 5.10			  19 Dec 2003			      dup2(3C)

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUES | ERRORS | ATTRIBUTES | SEE ALSO

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