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I have written a script that runs fine when executed locally:

./sysMole -time Aug 18 18

The arguments "-time", "Aug", "18", and "18" are successfully passed on to the script.

Now, this script is designed to be executed on a remote machine but, from a local directory on the local machine. Example:

ssh root@remoteServer "bash -s" < /var/www/html/ops1/sysMole

That also works fine. But the problem arises when I try to include those aforementioned arguments (-time Aug 18 18), for example:

ssh root@remoteServer "bash -s" < /var/www/html/ops1/sysMole -time Aug 18 18

After running that script I get the following error:

bash: cannot set terminal process group (-1): Invalid argument
bash: no job control in this shell

Please tell me what I'm doing wrong, this greatly frustrating. I've looked in multiple places for the answers. Any help is greatly appreciated.

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"Bash -s" is one of the ways you can execute an script from standard input (ie. a file). –  AllenD Aug 20 at 1:54

1 Answer

up vote 7 down vote accepted

You were pretty close with your example. It works just fine when you use it with arguments such as these.

Sample script:

$ more ex.bash 
#!/bin/bash

echo $1 $2

Example that works:

$ ssh serverA "bash -s" < ./ex.bash "hi" "bye"
hi bye

But it fails for these types of arguments:

$ ssh serverA "bash -s" < ./ex.bash "--time" "bye"
bash: --: invalid option
...

What's going on?

The problem you're encountering is that the argument, -time, or --time in my example, is being interpreted as a switch to bash -s. You can pacify bash by terminating it from taking any of the remaining command line arguments for itself using the -- argument.

Like this:

$ ssh root@remoteServer "bash -s" -- < /var/www/html/ops1/sysMole -time Aug 18 18

Examples

#1:

$ ssh serverA "bash -s" -- < ./ex.bash "-time" "bye"
-time bye

#2:

$ ssh serverA "bash -s" -- < ./ex.bash "--time" "bye"
--time bye

#3:

$ ssh serverA "bash -s" -- < ./ex.bash --time "bye"
--time bye

#4:

$ ssh  < ./ex.bash serverA "bash -s -- --time bye"
--time bye

NOTE: Just to make it clear that wherever the redirection appears on the command line makes no difference, because ssh calls a remote shell with the concatenation of its arguments anyway, quoting doesn't make much difference, except when you need quoting on the remote shell like in example #4:

$ ssh  < ./ex.bash serverA "bash -s -- '<--time bye>' '<end>'"
<--time bye> <end>
share|improve this answer
 
you are an Genius! What do I have to do to get to your level? I have alot of work cut out. Thanks so much. –  AllenD Aug 20 at 2:21
1  
@AllenD - just keep asking questions, and try and participate on the site as much as you can. I always try and learn something new each day. Before your question I didn't know how to do this either. 8-). Thanks for your question! –  slm Aug 20 at 2:25
2  
note that the redirection can appear at any point in the command: for example bash -s -- --time bye < ./ex.bash or even < ./ex.bash bash -s -- --time bye. this is because the shell first takes out the redirection instruction (regardless of where it is in the command), then sets up the redirection, then executes the rest of the command line with the redirection in place. –  lesmana Aug 20 at 9:30

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