xref: /illumos-gate/usr/src/man/man3elf/elf_hash.3elf (revision b210e77709da8e42dfe621e10ccf4be504206058)
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Copyright 1989 AT&T Copyright (c) 2001, Sun Microsystems, Inc. All Rights Reserved
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ELF_HASH 3ELF "Jul 11, 2001"
NAME
elf_hash - compute hash value
SYNOPSIS

cc [ flag ... ] file ... -lelf [ library ... ]
#include <libelf.h>

unsigned long elf_hash(const char *name);
DESCRIPTION

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).

ATTRIBUTES

See attributes(7) for descriptions of the following attributes:

ATTRIBUTE TYPE ATTRIBUTE VALUE
Interface Stability Stable
MT-Level MT-Safe
SEE ALSO

elf (3ELF), elf32_xlatetof (3ELF), elf_getdata (3ELF), libelf (3LIB), attributes (7)