http://www.perlmonks.org?node_id=807363


in reply to Re: C-like Pointers
in thread C-like Pointers

Thank you for your answer (and either thank to the others) :D

I know the fact, that C can only access virtual memory, I choosed the easier term "RAM" for people which don't know about Paging and stuff.

My real problem is to solve the following problem:

A buddy wrote a program in C which loads a ELF-kernel and execute it. I (I'm either a C progammer and OS-developer) wanted to write the same program in Perl, just for fun. The biggest problem is to access a virtual address within the process' memoryspace and using pointers to these addresses. I have to write this line:

krnl = mmap((void *)0x78000000, lof, PROT_READ, MAP_PRIVATE | MAP_FIXE +D, fileno(kernel), 0);

In Perl. My (not working) solution is:

$mapped_kernel = syscall(\&SYS_mmap, $address, $kernel_size, $page_rea +d, $map_private | $map_fixed, fileno(KERNEL), 0);

where syscall() and \&SYS_mmap are functions/references to functions from syscall.h (converted to .ph via h2ph), $kernel_size, $page_read, $map_private and $map_fixed simple integer-values, KERNEL the filehandle to the loaded kernel and $address the pointer to the address.

In short words, I want to do (void*)0x78000000 in Perl, a pointer to a address defiend by myself (without the help of C :-P). I've searched CPAN for XS and pointers but did not found anything related to my problem (or I was too stupid to find it ^^).