Get information stored inside executable files in a human readable way.
See all information:
readelf -a a.out
TODO understand all the information, and therefore the entire elf format.
To show only specific informations:
Symtable of elf, .o or .so.
Show only dependencies of an executable (symbols and shared libraries).
NEEDED: direct.sodependencies http://stackoverflow.com/questions/6242761/how-do-i-find-the-direct-shared-object-dependencies-of-a-linux-elf-binary..socan also depend on other.so. To recursively list all dependencies, useldd.
Hexdump section data for given section:
readelf -x .data hello_world.o
Sample output:
Hex dump of section '.data':
0x00000000 48656c6c 6f20776f 726c6421 0a Hello world!.
Don't limit the output width to 80 columns which is the default, and reduce the amount of 0 padding.
Makes things much more readable is your terminal is wide enough.
Without -W:
Section Headers:
[Nr] Name Type Address Offset
Size EntSize Flags Link Info Align
[ 0] NULL 0000000000000000 00000000
0000000000000000 0000000000000000 0 0 0
[ 1] .text PROGBITS 0000000000000000 00000040
000000000000005c 0000000000000000 AX 0 0 1
[ 2] .rela.text RELA 0000000000000000 000002f0
00000000000000d8 0000000000000018 I 11 1 8
[ 3] .data PROGBITS 0000000000000000 0000009c
0000000000000004 0000000000000000 WA 0 0 4
[ 4] .bss NOBITS 0000000000000000 000000a0
0000000000000000 0000000000000000 WA 0 0 1
[ 5] .rodata PROGBITS 0000000000000000 000000a0
0000000000000004 0000000000000000 A 0 0 1
[ 6] .comment PROGBITS 0000000000000000 000000a4
0000000000000025 0000000000000001 MS 0 0 1
[ 7] .note.GNU-stack PROGBITS 0000000000000000 000000c9
0000000000000000 0000000000000000 0 0 1
[ 8] .eh_frame PROGBITS 0000000000000000 000000d0
0000000000000058 0000000000000000 A 0 0 8
[ 9] .rela.eh_frame RELA 0000000000000000 000003c8
0000000000000030 0000000000000018 I 11 8 8
[10] .shstrtab STRTAB 0000000000000000 00000128
0000000000000061 0000000000000000 0 0 1
[11] .symtab SYMTAB 0000000000000000 00000190
0000000000000138 0000000000000018 12 10 8
[12] .strtab STRTAB 0000000000000000 000002c8
0000000000000025 0000000000000000 0 0 1
With -W:
Section Headers:
[Nr] Name Type Address Off Size ES Flg Lk Inf Al
[ 0] NULL 0000000000000000 000000 000000 00 0 0 0
[ 1] .text PROGBITS 0000000000000000 000040 00005c 00 AX 0 0 1
[ 2] .rela.text RELA 0000000000000000 0002f0 0000d8 18 I 11 1 8
[ 3] .data PROGBITS 0000000000000000 00009c 000004 00 WA 0 0 4
[ 4] .bss NOBITS 0000000000000000 0000a0 000000 00 WA 0 0 1
[ 5] .rodata PROGBITS 0000000000000000 0000a0 000004 00 A 0 0 1
[ 6] .comment PROGBITS 0000000000000000 0000a4 000025 01 MS 0 0 1
[ 7] .note.GNU-stack PROGBITS 0000000000000000 0000c9 000000 00 0 0 1
[ 8] .eh_frame PROGBITS 0000000000000000 0000d0 000058 00 A 0 0 8
[ 9] .rela.eh_frame RELA 0000000000000000 0003c8 000030 18 I 11 8 8
[10] .shstrtab STRTAB 0000000000000000 000128 000061 00 0 0 1
[11] .symtab SYMTAB 0000000000000000 000190 000138 18 12 10 8
[12] .strtab STRTAB 0000000000000000 0002c8 000025 00 0 0 1