The elf_hash() function computes a hash value, given a null terminated string, name. The returned hash value, h,
can be used as a bucket index, typically after computing h mod x to ensure appropriate bounds.
Hash tables may be built on one machine and used on another because elf_hash() uses unsigned arithmetic to avoid possible differences in various machines' signed arithmetic. Although name is shown as char* above, elf_hash() treats it as unsigned char* to avoid sign extension differences. Using char* eliminates type conflicts with expressions such as elf_hash(name).
ELF files' symbol hash tables are computed using this function (see elf_getdata(3ELF) and elf32_xlatetof(3ELF)). The hash value returned is guaranteed not to be the bit pattern of all ones ( ~0UL).
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