Berkeley CSUA MOTD:Entry 18595
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2025/07/09 [General] UID:1000 Activity:popular
7/9     

2000/7/6-7 [Computer/SW/Unix] UID:18595 Activity:high
7/5     Is there a way to get a shell (tcsh if it matters) to "steal" a job
        from another shell? Ie: I start process X (in the background) from
        shell 1; then the connection through which shell 1 was opened dies,
        but the shell apparently never receives a HUP and continues running,
        with the process running as well; I then log in again and want to
        somehow get that process in the foreground of my new shell.
        \_ use screen
           \_ thanks, but anything that can work post-facto?
              \_ No.  This is known as process migration.  Some research
                 OSes (Amoeba, I believe, maybe Plan 9? (don't think so))
                 can do this, but not Vanilla Unix-Like-OS.
                 \_ what the fuck? this is NOT called process migration.
                    process migration is hard because it involves moving
                    process ACROSS MACHINES. he just wants to talk to the
                    pty the process was running on. this is an easy problem
                    and screen solves it. you have to be REALLY stupid to
                    come up with a reply like yours.
                    \_ So screen will talk to a process that's already been
                       left without a tty?  What's the screen command for
                       that?
                       \_ No, it won't, but if you ran it in a screen window,
                          your terminal session could die and you could
                          reattach it later.  --dbushong
                \_ VMS (a non-research OS) did this 20 years ago.  It's no
                   big deal, just something Unix never picked up.
                   \_ i think it would be a pretty simple hack to linux to
                      do this. you need to reattach to the pty side of the
                      tty, and you need to change the pgroup of the process.
                      anything else involved? i'm guessing reattaching to
                      ptys needs a kernel hack. or maybe the mechanism is
                      already there. in either case, it's a simple hack.
                      someone should volunteer.
                        \_ That's the great thing about open source.  The
                           do-it-yourself nature.  Go do it.
                           \_ Yourself.
                      \_ Everyone always says i should volunteer for stuff
                             --Someone
                         \_ I always get blamed for everything
                             --Everyone
ERROR, url_link recursive (eces.Colorado.EDU/secure/mindterm2) 2025/07/09 [General] UID:1000 Activity:popular
7/9     

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