xref: /freebsd/contrib/elftoolchain/libelf/elf_hash.3 (revision 0b3105a37d7adcadcb720112fed4dc4e8040be99)
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24.\" $Id: elf_hash.3 189 2008-07-20 10:38:08Z jkoshy $
25.\"
26.Dd August 15, 2006
27.Os
28.Dt ELF_HASH 3
29.Sh NAME
30.Nm elf_hash
31.Nd compute a hash value for a string
32.Sh LIBRARY
33.Lb libelf
34.Sh SYNOPSIS
35.In libelf.h
36.Ft "unsigned long"
37.Fn elf_hash "const char *name"
38.Sh DESCRIPTION
39Function
40.Fn elf_hash
41computes a portable hash value for the null terminated string
42pointed to by argument
43.Ar name .
44.Pp
45The hash value returned is will be identical across
46machines of different architectures.
47This allows hash tables to be built on one machine and
48correctly used on another of a different architecture.
49The hash value returned is also guaranteed
50.Em not
51to be the bit pattern of all ones (~0UL).
52.Sh IMPLEMENTATION NOTES
53The library internally uses unsigned 32 bit arithmetic to compute
54the hash value.
55.Sh SEE ALSO
56.Xr elf 3 ,
57.Xr gelf 3
58