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NAME

rcp — remote file copy

SYNOPSIS

Copy Single File

rcp [-k realm] [-P] [-p] [-S size] [-R size] source_file1 dest_file

Copy Multiple Files

rcp [-k realm] [-P] [-p] [-S size] [-R size] source_file1 [source_file2]... dest_dir

Copy One or More Directory Subtrees

rcp [-k realm] [-P] [-p] [-S size] [-R size] -r source_dir1 [source_dir2]... dest_dir

Copy Files and Directory Subtrees

rcp [-k realm] [-P] [-p] [-S size] [-R size] -r file_or_dir1 [file_or_dir2]... dest_dir

DESCRIPTION

The rcp command copies files, directory subtrees, or a combination of files and directory subtrees from one or more systems to another. In many respects, it is similar to the cp command (see cp(1)).

To use rcp, you must have read access to files being copied, and read and search (execute) permission on all directories in the directory path.

In a Kerberos V5 Network Authentication environment, rcp uses the Kerberos V5 protocol while initiating the connection to a remote host. The authorization mechanism is dependent on the command line options used to invoke remshd on the remote host (i.e., -K, -R, -r, or -k). Kerberos authentication and authorization rules are described in the Secure Internet Services man page, sis(5).

Although Kerberos authentication and authorization may apply, the Kerberos mechanism is not applied when copying files. The files are still transferred in cleartext over the network.

Options and Arguments

rcp recognizes the following options and arguments:

source_file

source_dir

The name of an existing file or directory on a local or remote machine that you want copied to the specified destination. Source file and directory names are constructed as follows:

user_name@hostname:pathname/filename

or

user_name@hostname:pathname/dirname

Component parts of file and directory names are described below. If multiple existing files and/or directory subtrees are specified (source_file1, source_file2, ..., etc.), the destination must be a directory. Shell file name expansion is allowed on both local and remote systems. Multiple files and directory subtrees can be copied from one or more systems to a single destination directory with a single command.

dest_file

The name of the destination file. If host name and path name are not specified, the existing file is copied into a file named dest_file in the current directory on the local system. If dest_file already exists and is writable, the existing file is overwritten. Destination file names are constructed the same way as source files except that file name expansion characters cannot be used.

dest_dir

The name of the destination directory. If host name and path name are not specified, the existing file is copied into a directory named dest_dir in the current directory on the local system. If dest_dir already exists in the specified directory path (or current directory if not specified), a new directory named dest_dir is created underneath the existing directory named dest_dir. Destination directory names are constructed the same way as source directory tree names except that file name expansion characters cannot be used.

file_or_dir

If a combination of files and directories are specified for copying (either explicitly or by file name expansion), only files are copied unless the -r option is specified. If the -r option is present, all files and directory subtrees whose names match the specified file_or_dir name are copied.

-k realm

Obtain tickets from the remote host in the specified realm instead of the remote host's default realm as specified in the configuration file krb.realms.

-P

Disable Kerberos authentication. Only applicable in a secure environment based on Kerberos V5. If the remote host has been configured to prevent non-secure access, using this option would result in the generic error,

rcmd: connect: <hostname>: Connection refused

See DIAGNOSTICS in remshd(1M) for more details.

-p

Preserve (duplicate) modification times and modes (permissions) of source files, ignoring the current setting of the umask file creation mode mask. If this option is specified, rcp preserves the sticky bit only if the target user is superuser.

If the -p option is not specified, rcp preserves the mode and owner of dest_file if it already exists; otherwise rcp uses the mode of the source file modified by the umask on the destination host. Modification and access times of the destination file are set to the time when the copy was made.

-S size

This option sets the size of the socket send buffer.

-R size

This option sets the size of the socket receive buffer.

-r

Recursively copy directory subtrees rooted at the source directory name. If any directory subtrees are to be copied, rcp recursively copies each subtree rooted at the specified source directory name to directory dest_dir. If source_dir is being copied to an existing directory of the same name, rcp creates a new directory source_dir within dest_dir and copies the subtree rooted at source_dir to dest_dir/source_dir. If dest_dir does not exist, rcp creates it and copies the subtree rooted at source_dir to dest_dir.

Constructing File and Directory Names

As indicated above, file and directory names contain one, two, or four component parts:

user_name

Login name to be used for accessing directories and files on remote system.

hostname

Hostname of remote system where directories and files are located.

pathname

Absolute directory path name or directory path name relative to the login directory of user user_name.

filename

Actual name of source or destination file. File name expansion is allowed on source file names.

dirname

Actual name of source or destination directory subtree. File name expansion is allowed on source directory names.

Each file or directory argument is either a remote file name of the form hostname:path, or a local file name (with a slash (/) before any colon (:)). hostname can be either an official host name or an alias (see hosts(4)). If hostname is of the form ruser@rhost, ruser is used on the remote host instead of the current user name. An unspecified path (that is, hostname:) refers to the remote user's login directory. If path does not begin with /, it is interpreted relative to the remote user's login directory on hostname. Shell metacharacters in remote paths can be quoted with backslash (\), single quotes (''), or double quotes ("" ), so that they will be interpreted remotely.

rcp does not prompt for passwords. In a non-secure or traditional environment, user authorization is checked by determining if the current local user name or any user name specified via ruser exists on rhost. In a Kerberos V5 Network Authentication or secure environment, the authorization method is dependent upon the command line options for remshd (see remshd(1M) for details). In either case, remote command execution via remsh(1) and rcmd(3N) must be allowed and remshd(1M) must be executable on the remote host.

Third-party transfers in the form:

rcp ruser1@rhost1:path1 ruser2@rhost2:path2

are performed as:

remsh rhost1 -l ruser1 rcp path1 ruser2@rhost2:path2

Therefore, for a such a transfer to succeed, ruser2 on rhost2 must allow access by ruser1 from rhost1 (see hosts.equiv(4)).

WARNINGS

The rcp routine is confused by any output generated by commands in a .cshrc file on the remote host (see csh(1)).

Copying a file onto itself, for example:

rcp path `hostname`:path

may produce inconsistent results. The current HP-UX version of rcp simply copies the file over itself. However, some implementations of rcp, including some earlier HP-UX implementations, corrupt the file. In addition, the same file may be referred to in multiple ways, for example, via hard links, symbolic links, or NFS. It is not guaranteed that rcp will correctly copy a file over itself in all cases.

Implementations of rcp based on the 4.2BSD version (including the implementations of rcp prior to HP-UX 7.0) require that remote users be specified as rhost.ruser. If the first remote host specified in a third party transfer (rhost1 in the example below) uses this older syntax, the command must have the form:

rcp ruser1@rhost1:path1 rhost2.ruser2:path2

since the target is interpreted by rhost1. A common problem that is encountered is when two remote files are to be copied to a remote target that specifies a remote user. If the two remote source systems, rhost1 and rhost2, each expect a different form for the remote target, the command:

rcp rhost1:path1 rhost2:path2 rhost3.ruser3:path3

will certainly fail on one of the source systems. Perform such a transfer using two separate commands.

DIAGNOSTICS

Diagnostics can occur from both the local and remote hosts. Those that occur on the local host before the connection is completely established are written to standard error. Once the connection is established, any error messages from the remote host are written to standard output, like any other data.

Error! could not retrieve authentication type.

Please notify sys admin.

There are two authentication mechanisms used by rcp. One authentication mechanism is based on Kerberos and the other is not. The type of authentication mechanism is obtained from a system file which is updated by inetsvcs_sec(1M). If the system file does not contain known authentication types, the above error is displayed.

AUTHOR

rcp was developed by the University of California, Berkeley.

SEE ALSO

cp(1), ftp(1), remsh(1), remshd(1M), inetsvcs_sec(1M), rcmd(3N), hosts(4), hosts.equiv(4), sis(5).

ftp chapter in Using Internet Services.

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