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Why would Tomcat send a STOP signal to the console?

 
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Hello,

I'm running a Tomcat 5.0.30 Server on Win2k Pro, and I've been experiencing some hanging issues where any servlet or JSP page that tries to write to the standard output suddenly stops working. On the advice of our System Administrator I tried hitting CTRL+Q on the console window, and it "unhung" the system.

According to the sysadmin, this means that a STOP signal, or something similar, was sent to the console. How could this happen?

Thank you,
Yuriy
 
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Could it be that you accidently hit Ctrl-S first? I think (Unix oldtimers will correct me quickly if I'm wrong :-) those two key combinations work in conjunction to stop and start output to a console.
 
Yuriy Zilbergleyt
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Hi Ulf, thanks for the reply!

No, this isn't a one-time thing, it's been happening, seemingly at random, as we've been writing and testing the application, and I doubt we have been accidentally hitting CTRL+S. Also, the affect of the hang is slightly different from what's caused by CTRL+S. When the system is in our "hanging" state, CTRL+C serves to release it as well as CTRL+Q, and Tomcat continues on. But when the console is stopped deliberately with CTRL+S, CTRL+C closes the console window after all the pending output is flushed. Tomcat doesn't even catch this CTRL+C like it normally does for a graceful shutdown.

Thank you,
Yuriy
 
Yuriy Zilbergleyt
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Well, I changed catalina.bat to route all output (aside from first 4 lines) to a text files, and not a single hang so far. *crosses fingers*

-Yuriy
 
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