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from: @(#)chown.8 8.3 (Berkeley) 3/31/94
$NetBSD: chown.8,v 1.14 2023/05/20 00:54:15 pgoyette Exp $
.Dd May 19, 2023 .Dt CHOWN 8 .Os .Sh NAME .Nm chown .Nd change file owner and group .Sh SYNOPSIS .Nm .Oo .Fl R .Op Fl H | Fl L | Fl P .Oc .Op Fl dfhv .Ar owner Ns Op Ar :group .Ar .Nm .Oo .Fl R .Op Fl H | Fl L | Fl P .Oc .Op Fl dfhv .Ar :group .Ar .Nm .Oo .Fl R .Op Fl H | Fl L | Fl P .Oc .Op Fl dfhv .Fl Fl reference=rfile .Ar .Sh DESCRIPTION .Nm sets the user ID and/or the group ID of the specified files. Symbolic links named by arguments are silently left unchanged unless .Fl h is used.
p The options are as follows: l -tag -width Ds t Fl H If the .Fl R option is specified, symbolic links on the command line are followed. (Symbolic links encountered in the tree traversal are not followed.) t Fl L If the .Fl R option is specified, all symbolic links are followed. t Fl P If the .Fl R option is specified, no symbolic links are followed. t Fl R Change the user ID and/or the group ID for the file hierarchies rooted in the files instead of just the files themselves. t Fl d Do not attempt to update a file's owner or group or its set-user-id and set-group-id bits if they are all already set to the desired values. t Fl f Do not report any failure to change file owner or group, nor modify the exit status to reflect such failures. t Fl h If .Ar file is a symbolic link, the owner and/or group of the link is changed. t Fl v Cause .Nm to be verbose, showing files as they are processed. .El
p The .Fl H , .Fl L and .Fl P options are ignored unless the .Fl R option is specified. In addition, these options override each other and the command's actions are determined by the last one specified. The default is as if the .Fl P option had been specified.
p The .Fl L option cannot be used together with the .Fl h option.
p The .Ar owner and .Ar group operands are both optional, however, one must be specified; alternatively, both the owner and group may be specified using a reference .Ar rfile specified using the .Fl Fl reference argument. If the .Ar group operand is specified, it must be preceded by a colon (``:'') character.
p The .Ar owner may be either a user name or a numeric user ID. The .Ar group may be either a group name or a numeric group ID. Since it is valid to have a user or group name that is numeric (and does not have the numeric ID that matches its name) the name lookup is always done first. Preceding an ID with a ``#'' character will force it to be taken as a number.
p The ownership of a file may only be altered by a super-user for obvious security reasons.
p Unless invoked by the super-user, .Nm clears the set-user-id and set-group-id bits on a file to prevent accidental or mischievous creation of set-user-id and set-group-id programs. .Sh EXIT STATUS .Ex -std chown .Sh COMPATIBILITY Previous versions of the .Nm utility used the dot (``.'') character to distinguish the group name. This has been changed to be a colon (``:'') character so that user and group names may contain the dot character. .Sh SEE ALSO .Xr chflags 1 , .Xr chgrp 1 , .Xr find 1 , .Xr chown 2 , .Xr lchown 2 , .Xr fts 3 , .Xr symlink 7 .Sh STANDARDS The .Nm command is expected to be POSIX 1003.2 compliant.
p The .Fl v and .Fl d options and the use of ``#'' to force a numeric lookup are extensions to .St -p1003.2 . .Sh HISTORY A .Nm utility appeared in .At v1 .
Indexes created Wed Sep 24 15:09:51 GMT 2025