Imagine a shell script on the remote server as
#!/bin/bash
rm /test.x
How can I (if possible) to execute this script from my local machine to delete /test.x file on my local machine. Obviously, the solution should be with something like ssh authorization, but without downloading the script file from the remote server.
In fact, I want to use the remote script as a provider of shell commands to be run on the local machine.
You'll need to download the content of the script in some way. You could do
ssh remote-host cat script.bash | bash
But that would have the same kind of problem as:
cat script.bash | bash
namely that stdin within the script would be the script itself (which could be an issue if commands within the script need to get some input from the user).
Then, a better alternative (but you'd need a shell with support for process substitution like ksh, zsh or bash) would be:
bash <(ssh remote-host cat script.bash)
Both approaches do download the script in that they retrieve its content, but they don't store it locally. Instead the content is fed to a pipe whose other end is read and interpreted by bash.
You can also have the content of the remote script executed in the current bash process with:
eval "$(ssh remote-host cat script.bash)"
But that downloads the script fully (and stores it in memory) before running it.
The obvious solution would be to do:
. <(ssh remote-host cat script.bash)
But beware that some versions of bash have issues with that.
bash is quite, as it' my default. Seems a subtle and practical solution.
Commented
Jan 19, 2013 at 21:06
Mount the remote filesystem containing the script with sshfs. This makes the script a local file which you know how to execute.
mkdir /path/to/remote-host
sshfs remote-host:/ /path/to/remote-host
/path/to/remote-host/path/to/script
This is an old question but appeared as one of the first hits on google so here is an update years later.
This can be done on a single line using scp:
scp remote-host@/full-path/script.sh . && ./script.sh
The file is copied from the remote host to the current working directory then executed from the current working directory
/path/to/nfs/mount/script.shfrom the local machine. The local machine's/test.xfile will be removed.but without downloading the script file from the remote server: How do you expect the remote script to work on your local machine without sending the script content to the local machine ?!?commandssomehow, instead of downloading the entire script and executing it locally.setto see that). You won't gain anything by trying to send the bare minimum to make the command work. Just think about the dependency hell if commanddo_thatdepends ondo_thisto work properly. You could still do it proxy-style (e.g.do_that () { download_do_that_definition_from_server && do_that; }), but it's still much more complicated than downloading the entire script and feeding it directly into the interpreter.