c - Signal Stack

Question

I did read that signals need to have a separate stack, why and how do you think it is implemented ?

Are they dynamically allocated or statically allocated ? How is memory allocation done ? Is it the same for all signals ?

Answer 1

The reason that signals need a separate stack is that, if the normal stack gets corrupted or overflows, the signal can still execute. I think the signal stack is usually allocated dynamically, but it could implemented be either way. You can set a new signal stack with sigaltstack. It is the same for all signals.

Answer 2

另一个更深奥的原因是创建用户级线程。请参阅 Ralf Engelschall 的论文“便携式多线程”：http ://www.gnu.org/software/pth/rse-pmt.ps 。它描述了如何使用“信号栈蹦床技巧”来影响用户空间线程。