Cygwin program (sshpass) produces no output when used in Windows command prompt

cygwin;

I have built sshpass on Cygwin. It works perfectly from within a Cygwin terminal window:

sshpass -p password ssh -o StrictHostKeyChecking=no user@host

However, the exact same command from a Windows command prompt produces no output.

I tried a non-interactive command to see if that worked but it didn't:

sshpass -p password ssh -o StrictHostKeyChecking=no user@host ls

Both work fine from the Cygwin environment but not from a Windows command prompt. They do work from the Windows command prompt but there is no output. I know this because I can issue commands from a cmd.exe window and see the effects on the remote host. Also, plain ssh (the Cygwin one) works fine from the Windows command prompt.

How can I get output from sshpass when used in a Windows command prompt ?

Best Answer

The reason that this does not work is due to an incompatibility in stdin/stdout redirection between cygwin and native Win32 programs but there is a wrapper program called cygnative which solves the problem. It allows the desired command-line to be used like this:

C:> cygnative sshpass -p password ssh -o StrictHostKeyChecking=no user@host ls

(this works for non-interactive commands but not for interactive terminal sessions)

The original author's links to cygnative.exe are dead, but it is available as C source in this gist or as source and executable in this zip.

I discovered this solution when trying to solve another problem, this time trying to use rsync over PuTTY's plink program. I was getting an error:

Unable to read from standard input: The parameter is incorrect.

which led me to discover cygnative, but tracking it down was difficult due to the original links being dead.

The problem is described here and presents the solution, cygnative, here, with an updated version 1.2 here.

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