object-files

From what I understand, instructions and data in an object file all have addresses. First data item start at address 0 and first instruction also start at address 0. The relocation table contains information about instructions that need to be updated if the addresses in the file change, for example if the file is linked together with another. Line A, in the example below, would be in the relocation table. I don't think B would be in the relocation table, since the address of label "equal" is relative to B. Are these correct assumptions? I know the symbol table show the labels the file have and

This question already has an answer here: What's an object file in C? 5 answers I was asked a question: "What is an 'object file'?". After looking at Wiki , I only know that it contains objects . But what are those objects and why someone called them that way? Object files (or object code) are machine code files generated by a compiler from source code. The difference with an executable is that the object file isn't linked, so references to functions, symbols, etc aren't defined yet (their memory addresses is basically left blank). When you compile a C file with GCC: gcc -Wall -o test test.c

I'm currently writing a C++ application which implements an Oscillator in conjuction with math.h. The code I have should work fine for the application (trying to compile an object file), bu I'm getting a compiler error most likely having to do with syntax/etc; I think it has something to do with namespace. The error: Terminal Output: User-Name-Macbook-Pro:Synth Parts UserName$ make g++ -o Oscillators.o -c -I. Oscillators.cpp -c In file included from Oscillators.cpp:2: /usr/include/math.h:41: error: expected unqualified-id before string constant In file included from /usr/include/c++/4.2.1/bits

what is the relation between shared object( .so ) file and object( .o ) file? can you please explain via example? quark Let's say you have the following C source file, call it name.c #include <stdio.h> #include <stdlib.h> void print_name(const char * name) { printf("My name is %s\n", name); } When you compile it, with cc name.c you generate name.o . The .o contains the compiled code and data for all functions and variables defined in name.c, as well as index associated their names with the actual code. If you look at that index, say with the nm tool (available on Linux and many other Unixes)

How can I view symbols in a .o file? nm does not work for me. I use g++/linux. Instead of nm , you can use the powerful objdump . See the man page for details. Try objdump -t myfile or objdump -T myfile . With the -C flag you can also demangle C++ names, like nm does. Have you been using a cross-compiler for another platform? If so, you need to use the respective nm or objdump commmand. For example, if you have used XXX-YYY-gcc to compile the .o file, you need to use XXX-YYY-nm or XXX-YYY-objdump to process the files. There is a command to take a look at which functions are included in an