elf

Ulrich Drepper's paper on thread-local storage outlines the TLS ABI for several different cpu architectures, but I'm finding it insufficient as a basis for implementing TLS for two reasons: It omits a number of important archs like ARM, MIPS, etc. (while including a bunch of completely-irrelevant ones like Itanium) More importantly, it mixes a lot of implementation details with ABI, so that it's hard to tell which properties are required for interoperability, and which are just aspects of his implementation. As an example, the only actual ABI requirements for i386 are: %gs:0 points to a

Is it possible to run the COFF executable files on UNIX or the ELF executable files on Windows? And what would be the steps to be able to run either file type on Windows and UNIX. I'm just curious. To actually run executables and have them do useful stuff, you need to worry about the API, not just the executable file format. On a Linux machine with WINE installed, you can run Windows .EXE files from the command line and they do the same thing that they do on Windows. The other way around is not really possible, however if you install CYGWIN on a Windows machine, and then rebuild the

I'm studying the ELF file format, so I compiled a small program, dumped the section headers and their contents from the resulting executable. The ELF header contains the entry point address, which points into start of the .text section. I also found the .data section that contains the static data and .rodata that contains the read only data... I expect there is a section for the stack too, but I can't find that section. I also expect that at some point ESP is set to the top of some section but I can't find anything like that in the disassembly. So how does ESP gets its initial value? The

In ELF binary, how to change the alignment of loadable segments? In the below example (See right corner), I want to reduce the 0x200000 to 0x40960. LOAD 0x000000 0x000000400000 0x0000000000400000 0x000704 0x000704 R E **0x200000** LOAD 0x000e10 0x000000600e10 0x0000000000600e10 0x000230 0x000238 RW **0x200000** Can any compiler expert (GCC or clang), provide me a solution for this? I don't know if you really want to do that but you can change the max page size with ld -z max-page-size=4096 : $ gcc foo.c && readelf -Wl ./a.out | grep LOAD LOAD 0x000000 0x0000000000400000 0x0000000000400000

I am having a problem about a wrong symbol resolution. My main program loads a shared library with dlopen and a symbol from it with dlsym. Both the program and the library are written in C. Library code int a(int b) { return b+1; } int c(int d) { return a(d)+1; } In order to make it work on a 64-bit machine, -fPIC is passed to gcc when compiling. The program is: #include <dlfcn.h> #include <stdio.h> int (*a)(int b); int (*c)(int d); int main() { void* lib=dlopen("./libtest.so",RTLD_LAZY); a=dlsym(lib,"a"); c=dlsym(lib,"c"); int d = c(6); int b = a(5); printf("b is %d d is %d\n",b,d); return 0;