Thanks Dave your reply answered the question where they declared. But how does these variables get the segment address of data and bss for a running process to make a copy to the child process? This is the questions which is a puzzle to me.
Thanks in Advance for your answer Sudha On 1/20/06, Dave Korn <[EMAIL PROTECTED]> wrote: > Sudhahar wrote: > > > from parent process to child process. After trying to find where the > > data_start and data_end get the address of running process data and > > bss segment, I ended up with a declaration of > > > > extern char _data_start__, _data_end__, _bss_start__, _bss_end__; in > > file Winsup.h > > > > There is no other place where _data_start__, _data_end__, > > _bss_start__, _bss_end__ are defined they act as external symbols for > > cygwin. > > > > Can anyone through some light on where these variables are actually > > declared and how they get the running process segment addresses. > > They are generated by the linker. Take a look at the linker script by > running "ld --verbose". > > [EMAIL PROTECTED] /usr/build/src-binutils/bfd> ld --verbose | grep _start > to include this between __data_start__ and __data_end__, but that > __data_start__ = . ; > __bss_start__ = . ; > ___crt_xc_start__ = . ; > ___crt_xi_start__ = . ; > ___crt_xl_start__ = . ; > ___crt_xp_start__ = . ; > ___crt_xt_start__ = . ; > ___tls_start__ = . ; > [EMAIL PROTECTED] /usr/build/src-binutils/bfd> ld --verbose | grep _end > to include this between __data_start__ and __data_end__, but that > ".data_cygwin_nocopy" and explictly include it after __data_end__. */ > __data_end__ = . ; > __bss_end__ = . ; > ___crt_xc_end__ = . ; > ___crt_xi_end__ = . ; > /* ___crt_xl_end__ is defined in the TLS Directory support code */ > ___crt_xp_end__ = . ; > ___crt_xt_end__ = . ; > ___tls_end__ = . ; > PROVIDE ( _end = .); > __end__ = .; > [EMAIL PROTECTED] /usr/build/src-binutils/bfd> > > > cheers, > DaveK > -- > Can't think of a witty .sigline today.... > > > -- > Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple > Problem reports: http://cygwin.com/problems.html > Documentation: http://cygwin.com/docs.html > FAQ: http://cygwin.com/faq/ > > -- Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple Problem reports: http://cygwin.com/problems.html Documentation: http://cygwin.com/docs.html FAQ: http://cygwin.com/faq/
