Run process with gdb and detach it -

is possible run process gdb, modify memory , detach process afterwards?

i can't start process outside of gdb need modify memory, before first instruction executed.

when detach process started gdb, gdb hang, killing gdb process makes debugged process still running.

i use following script launch process:

echo '# custom gdb function finds entry_point assigns $entry_point_address entry_point b *$entry_point_address run set *((char *)0x100004147) = 0xeb set *((char *)0x100004148) = 0xe2 detach # gdb hangs here quit # quit never gets executed ' | gdb -quiet "$file" 

this happens in both of gdb versions:

gnu gdb 6.3.50-20050815 (apple version gdb-1824) gnu gdb 6.3.50-20050815 (apple version gdb-1822 + reverse.put.as patches v0.4) 

i'm pretty sure can't detach inferior processes started directly under gdb, however, following might work you, based on recent gdb, don't know how of work on version 6.3.

create small shell script, this:

#! /bin/sh echo $$ sleep 10 exec /path/to/your/program arg1 arg2 arg3 

now start up, spot pid echo $$, , attach shell script gdb -p pid. once attached can:

(gdb) set follow-fork-mode child (gdb) catch exec (gdb) continue continuing. [new process new-pid] process new-pid executing new program: /path/to/your/program [switching process new-pid]  catchpoint 1 (exec'd /path/to/your/program), 0x00007f40d8e9fc80 in _start () (gdb) 

you can modify child process required. once you're finished do:

(gdb) detach 

and /path/to/your/program should resume (or start in case) running.