Pause a process execution from external program

[Pintu Agarwal]

Hi All,
I was just wondering if this is possible in the Linux world.
My requirement is:
For some reason, I want to halt/pause the execution (for some
specified time) of a running process/thread (at some location),
without modified the source, may be by firing some events/signals from
an another external program, by specifying the address location or a
line number.

Is this possible ?
May be by using some system call, or other mechanism using the process PID.
Assume that its a debugging system with all root privileges.

Basically, its just like how "gdb" is able to set the break-point in a
program, and able to stop its execution exactly at that location.
I am wondering what mechanism "gdb" uses to do this?
I tried to check here, but could find the exact place, where this is handled:
https://github.com/bminor/binutils-gdb/blob/master/gdb/breakpoint.c

Unfortunately, I cannot use "gdb", but I wanted to borrow this
mechanism only to serve my purpose.

If anyone is aware, please let me know.
I will share my findings here, after I get some useful results of my
experimentation.

Thank you for your help!


Regards,
Pintu