topic Re: rcp or cp on same machine, any difference in Operating System - HP-UX

rcp or cp on same machine, any difference

makp — Tue, 19 Aug 2008 04:38:15 GMT

Hi,

Is there any difference if I use rcp instead of cp on same machine for copying large files?

Apreicate if someone can throw some lights.

Thanks

Re: rcp or cp on same machine, any difference

Rajeev Shukla — Tue, 19 Aug 2008 05:23:29 GMT

cp is more prefered on the same system (localhost) coz rcp goes through al the authentication checks and would happen over the NIC where as cp is internal.
In short rcp will take a bit longer compared to cp in localhost

Re: rcp or cp on same machine, any difference

Gokul Chandola — Tue, 19 Aug 2008 05:27:13 GMT

Hi,

There are many differences within these two methods, hint is following.

*)The NFS CP will bring the source file into the buffer cache, _and_ will have the destination file in the buffer cache. The rcp will only bring the source file into the buffer cache.

*) rcp is over TCP

Regards,
Gokul Chandola

Re: rcp or cp on same machine, any difference

SKR_1 — Tue, 19 Aug 2008 06:18:27 GMT

rcp is used for remote copy from another server to server in which you are logged in or vice versa.

Thanks

SKR

Re: rcp or cp on same machine, any difference

Sajjad Sahir — Mon, 04 May 2009 10:20:59 GMT

rcp means remote copy
cp means copying

rcp is mainly using to copy from system to anohter

while cp is using internal in system

thanks and regards

Sajjad Sahir

Re: rcp or cp on same machine, any difference

Steven E. Protter — Mon, 04 May 2009 10:24:11 GMT

Shalom,

rcp between machines

cp within one system.

cp is a bit more reliable.

rcp won't copy properly to the same system. Why would you use it to run a local copy through the system NIC card?

SEP

Re: rcp or cp on same machine, any difference

Pete Randall — Mon, 04 May 2009 10:32:24 GMT

Why not start by looking at the man page:

rcp(1) rcp(1)

NAME
rcp - remote file copyDESCRIPTION
The rcp command copies files, directory subtrees, or a combination of files and directory subtrees from one or more systems to another.

After reading that, I wouldn't even think to use it within one system. I mean, "why"????

Pete

Re: rcp or cp on same machine, any difference

Laurent Menase — Mon, 04 May 2009 12:07:46 GMT

If you mean
between
rcp
cp from or to NFS

Then rcp is usually better as it sends directly the file from buffercache to the socket.

cp will cause a copy from buffercache to user space, hen from userspace to buffercache, then from buffercache over NFS to the remote system, then to disk