$home/manuals/plan9_2nd/2/dup

DUP(2)                        System Calls Manual                       DUP(2)



NAME
       dup - duplicate an open file descriptor

SYNOPSIS
       #include <u.h>
       #include <libc.h>

       int dup(int oldfd, int newfd)

DESCRIPTION
       Given  a file descriptor, oldfd, referring to an open file, dup returns
       a new file descriptor referring to the same file.  If newfd is  in  the
       range  of legal file descriptors dup will use that for the new file de‐
       scriptor (closing any old file associated with newfd); if newfd  is  -1
       the system chooses the lowest available file descriptor.

SOURCE
       /sys/src/libc/9syscall

SEE ALSO
       intro(2), dup(3)

DIAGNOSTICS
       Sets errstr.



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