A few simple concept notes

1. Re-positioning

The assembler produces a target program that contains at least three extents, that is, the text area, the data area, and the BSS area. The text area typically includes code and constants for the program, the data area typically holds global variables, and the BSS is used to store uninitialized variables or as a public variable storage space. In a target file, its text area starts with address 0, followed by the data area, followed by the BSS area. To run the program, it must be loaded into memory, so the addresses of these zones need to be rearranged in memory, that is, relocation.

2. Linker and Loader

The linker resolves an external memory address problem, and the loader puts all executable target files into memory for execution.

A few simple concept notes