Aliasing text and data segments of a process

[Wolfgang Rupprecht]

In article <207 at sdti.UUCP> mjy at sdti.UUCP (0000-Michael J. Young) writes:
>Actually, setting breakpoints is no problem even with the other three types.
>That's what the ptrace(2) system call is for.

If you have a shared-text type of executable, you can't guarentee
ptrace-ability. If someone else is executing the same text, the system
is forced to deny you write-permission with the error 'text busy'.
(Otherwise the other process would also get hit with the breakpoints.)
The other process can still be corrupted however, if it is started
*after* you insert the breakpoints. Now it gets amusing, since you
can't *remove* the breakpoints once the other process is started.
--
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