| dup.2 (108087) | dup.2 (131504) |
|---|---|
| 1.\" Copyright (c) 1980, 1991, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. --- 16 unchanged lines hidden (view full) --- 25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30.\" SUCH DAMAGE. 31.\" 32.\" @(#)dup.2 8.1 (Berkeley) 6/4/93 | 1.\" Copyright (c) 1980, 1991, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. --- 16 unchanged lines hidden (view full) --- 25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30.\" SUCH DAMAGE. 31.\" 32.\" @(#)dup.2 8.1 (Berkeley) 6/4/93 |
| 33.\" $FreeBSD: head/lib/libc/sys/dup.2 108087 2002-12-19 09:40:28Z ru $ | 33.\" $FreeBSD: head/lib/libc/sys/dup.2 131504 2004-07-02 23:52:20Z ru $ |
| 34.\" 35.Dd June 4, 1993 36.Dt DUP 2 37.Os 38.Sh NAME 39.Nm dup , 40.Nm dup2 41.Nd duplicate an existing file descriptor --- 12 unchanged lines hidden (view full) --- 54duplicates an existing object descriptor and returns its value to 55the calling process 56.Fa ( newd 57= 58.Fn dup oldd ) . 59The argument 60.Fa oldd 61is a small non-negative integer index in | 34.\" 35.Dd June 4, 1993 36.Dt DUP 2 37.Os 38.Sh NAME 39.Nm dup , 40.Nm dup2 41.Nd duplicate an existing file descriptor --- 12 unchanged lines hidden (view full) --- 54duplicates an existing object descriptor and returns its value to 55the calling process 56.Fa ( newd 57= 58.Fn dup oldd ) . 59The argument 60.Fa oldd 61is a small non-negative integer index in |
| 62the per-process descriptor table. The value must be less | 62the per-process descriptor table. 63The value must be less |
| 63than the size of the table, which is returned by 64.Xr getdtablesize 2 . 65The new descriptor returned by the call 66is the lowest numbered descriptor 67currently not in use by the process. 68.Pp 69The object referenced by the descriptor does not distinguish 70between --- 20 unchanged lines hidden (view full) --- 91.Xr open 2 92system call. 93The close-on-exec flag on the new file descriptor is unset. 94.Pp 95In 96.Fn dup2 , 97the value of the new descriptor 98.Fa newd | 64than the size of the table, which is returned by 65.Xr getdtablesize 2 . 66The new descriptor returned by the call 67is the lowest numbered descriptor 68currently not in use by the process. 69.Pp 70The object referenced by the descriptor does not distinguish 71between --- 20 unchanged lines hidden (view full) --- 92.Xr open 2 93system call. 94The close-on-exec flag on the new file descriptor is unset. 95.Pp 96In 97.Fn dup2 , 98the value of the new descriptor 99.Fa newd |
| 99is specified. If this descriptor is already in use and | 100is specified. 101If this descriptor is already in use and |
| 100.Fa oldd 101\*(Ne 102.Fa newd , 103the descriptor is first deallocated as if the 104.Xr close 2 105system call had been used. 106If 107.Fa oldd --- 57 unchanged lines hidden --- | 102.Fa oldd 103\*(Ne 104.Fa newd , 105the descriptor is first deallocated as if the 106.Xr close 2 107system call had been used. 108If 109.Fa oldd --- 57 unchanged lines hidden --- |