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bss

The part of a program that holds global variables starting at zero; the file only records its size, and the system supplies the zeros.

The bss section (.bss on ELF and COFF, __DATA,__bss on Mach-O) reserves zero-initialized static storage; it occupies no bytes in the file, only a size, and is filled with zeros when the program is loaded.

Examples

  • long scratch[512]; at file scope goes in bss: 4,096 bytes in memory, none of them in the file.

See also

memory map ELF Mach-O PE
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