Prev: What's the point of using tar *for backup* today?
Next: Q. How do I get bash to respect my physical directory structure?
From: sysdrk on 5 Jan 2010 10:29
I have a lot of files I need to copy to another server using scp
(secure copy). For efficiency reasons I want to minimize the number
of scp invocations. So, logically I would like to do this:

find ... [files] | xargs -i scp {} user(a)server:/somedir

Unfortunately, I have to use the replacement string {} since I need to
provide a directory as the last parameter to scp. However, this
causes xargs to invoke scp for each individual file.

I can see doing this using a double xargs like this:

find ... [files] | xargs echo scp user(a)server:/somedir |
sed 's/.*somedir//' |
xargs -i scp {} user(a)server:/somedir

Here the first xargs is used to put as many files together on a single
line as possible and then the second xargs is used to feed each line
of files into an scp.

Is there a better way to do this? Somehow it seems like there should
be a way to get xargs to do this with a single xargs but I haven't
seen a way.

Denis
From: Ben Bacarisse on 5 Jan 2010 11:55
sysdrk <sysdrk(a)wowway.com> writes:

> I have a lot of files I need to copy to another server using scp
> (secure copy). For efficiency reasons I want to minimize the number
> of scp invocations. So, logically I would like to do this:
>
> find ... [files] | xargs -i scp {} user(a)server:/somedir
>
> Unfortunately, I have to use the replacement string {} since I need to
> provide a directory as the last parameter to scp. However, this
> causes xargs to invoke scp for each individual file.

If your names are "space safe" (it seems so from your example) then

find ... | xargs | xargs -i scp {} user(a)server:/somedir

may do what you want.

--
Ben.
From: Bill Marcum on 5 Jan 2010 11:34
On 2010-01-05, sysdrk <sysdrk(a)wowway.com> wrote:
>
> I can see doing this using a double xargs like this:
>
> find ... [files] | xargs echo scp user(a)server:/somedir |
> sed 's/.*somedir//' |
> xargs -i scp {} user(a)server:/somedir
>
> Here the first xargs is used to put as many files together on a single
> line as possible and then the second xargs is used to feed each line
> of files into an scp.
>
> Is there a better way to do this? Somehow it seems like there should
> be a way to get xargs to do this with a single xargs but I haven't
> seen a way.
>
You could use xargs to call a script or function that takes the
destination as the first argument and calls scp.

scp_to () {
dest="$1"
shift
scp "$@" "$dest"
}
From: Icarus Sparry on 5 Jan 2010 12:29
On Tue, 05 Jan 2010 16:55:55 +0000, Ben Bacarisse wrote:

> sysdrk <sysdrk(a)wowway.com> writes:
>
>> I have a lot of files I need to copy to another server using scp
>> (secure copy). For efficiency reasons I want to minimize the number of
>> scp invocations. So, logically I would like to do this:
>>
>> find ... [files] | xargs -i scp {} user(a)server:/somedir
>>
>> Unfortunately, I have to use the replacement string {} since I need to
>> provide a directory as the last parameter to scp. However, this causes
>> xargs to invoke scp for each individual file.
>
> If your names are "space safe" (it seems so from your example) then
>
> find ... | xargs | xargs -i scp {} user(a)server:/somedir
>
> may do what you want.

Other options you might consider
1) Use something like cpio, pax or a "tar" that can read the list of
files from standard input. Then use "ssh" rather than "scp" to create a
pipeline like
find ... | pax -w | ssh user(a)server 'cd /somedir; pax -r'

2) Write your own wrapper for scp that reorders the arguments, e.g. myscp
#!/bin/sh
dest=$1
shift
scp "$@" "$dest"

and then use
find ... | xargs myscp user(a)server:/somedir

Of course you don't actually need to create your own script to do this,
you can use
find ... | xargs sh -c 'scp "$@" user(a)somehost:/somedir' dummy_arg0
but I think another file is cleaner, and you don't need to worry if you
need the dummy_arg0 or not.
From: Karsten Kruse on 5 Jan 2010 14:34
sysdrk schrieb:

> I have a lot of files I need to copy to another server using scp
> (secure copy). For efficiency reasons I want to minimize the number
> of scp invocations. So, logically I would like to do this:

> find ... [files] | xargs -i scp {} user(a)server:/somedir

> Unfortunately, I have to use the replacement string {} since I need to
> provide a directory as the last parameter to scp. However, this
> causes xargs to invoke scp for each individual file.

If the list of files is short, without spaces and such, try this:

scp $(find ...) user(a)server:/somedir

Otherwise try this:

find ... | tar -c | ssh user(a)host 'tar -x -C /targetdir'

Karsten

--

() My homepage is http://www.tecneeq.de/ and your homepage sucks�!
<\/>
_/\_ �) Unless it has animated gifs from 1996, then it rocks!
 |  Next  |  Last
Pages: 1 2
Prev: What's the point of using tar *for backup* today?
Next: Q. How do I get bash to respect my physical directory structure?