> Can you actually substantiate your 85% confident claim? I unfortunately can't, it was apparently added in 2.1.57, which would be somewhere around 1998~1999.

> Can you actually substantiate your 85% confident claim? I unfortunately can't, it was apparently added in 2.1.57, which would be somewhere around 1998~1999. I started working with Linux around 2001~2002, and this association of PDEATHSIG with LinuxThreads has at some point embedded itself into my brain… I can't reconstruct when or why. And I can't seem to find the specific patch that added PDEATHSIG, and can't find a versioned history of LinuxThreads either… Probably best to treat my comment as "grandpa tells weird stories that may or may not be true" :'( [… I'm not even that old T_T] Best reference I can find is in MAINTAINERS: N: Richard E. Gooch E: rgooch@atnf.csiro.au D: parent process death signal to children D: prctl() syscall S: CSIRO Australia Telescope National Facility S: P.O. Box 76, Epping S: N.S.W., 2121 S: Australia [ed.] wait! — https://man7.org/conf/piter2019/once_upon_an_API-Linux-Piter-2019-Kerrisk.pdf https://man7.org/conf/piter2019/once_upon_an_API-Linux-Piter... "(Of course, there was no explanation of why the feature was needed)" Note Richard was at minimum involved in discussions about LinuxThreads: https://lkml.iu.edu/hypermail/linux/kernel/9806.2/1227.html https://lkml.iu.edu/hypermail/linux/kernel/9806.2/1227.html — and it does mention prctl and "dying main thread"…