COP 3402 meeting -*- Outline -*-

* Executable Files

** Sections of Executable Files
------------------------------------------
        SECTIONS OF EXECUTABLE FILES

(header: info about each section)

Text Section:


Data Section:


Relocation Section:




(debugging sections:
   symbol table section: global labels
   debugging section: file + line info
------------------------------------------
     ... executable instructions (binary format)

     ... data in binary format

     ... identifies locations needing adjustment
         when program is moved in memory

     See https://refspecs.linuxfoundation.org/elf/elf.pdf
        for details

------------------------------------------
        EXECUTABLE ELF FILE LAYOUT

  |------------------------|
  [ General info           ] (header
  [ Program name           ]  section)
  [ Start address of text  ]
  [ Length of text section ]
  [ Start address of data  ]
  [ Length of data section ]
  [ Start address of reloc.]
  [ Length of reloc. sect. ]
  |------------------------|
  |                        |
  |                        |
  |    Text Section        |
  |                        |
  |                        |  
  |------------------------|
  |                        |
  |                        |
  |    Data Section        |
  |                        |
  |                        |  
  |------------------------|
  |                        |
  |                        |
  |    Relocation Section  |
  |                        |
  |                        |  
  |------------------------|

------------------------------------------
   (The above is somewhat simplified from reality)

** Relocation
------------------------------------------
     RELOCATION OF EXECUTABLE FILES

Assemblers generate code assuming
   starting address is 0

Relocation data identifies
  parts of instructions that need offset
  added if the starting address is
    changed to 0 + offset
------------------------------------------