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.\" Copyright (c) 2016 Dag-Erling Smørgrav
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.Dd January 8, 2016
.Dt CRYB_ADLER32 3
.Os
.Sh NAME
.Nm cryb_adler32_hash
.Nd hash functions
.Sh LIBRARY
.Lb libcryb-hash
.Sh SYNOPSIS
.In stddef.h
.In stdint.h
.In cryb/hash.h
.Ft uint32_t
.Fn cryb_adler32_hash "const void *data" "size_t len"
.Sh DESCRIPTION
The
.Fn cryb_adler32_hash
function returns a 32-bit checksum of the
.Va len
first bytes of the object pointed to by
.Va data
using the Adler-32 algorithm described in RFC 1950.
.Pp
Unlike the Pearson hash implemented by
.Fn cryb_pearson_hash
or cryptographic message digests such as the SHA family, these
checksums are suitable for error detection.
.Sh IMPLEMENTATION NOTES
The
.In cryb/hash.h
header provides macros which allows these functions to be referred to
without their
.Dq Li cryb_
prefix.
.Sh SEE ALSO
.Xr cryb_hash 3
.Sh REFERENCES
.Rs
.%A "Deutsch, P."
.%A "Gailly, J.-L."
.%D "May 1996"
.%R "ZLIB Compressed Data Format Specification version 3.3"
.%O "RFC 1950"
.Re
.Sh AUTHORS
The
.Fn cryb_adler32_hash
function and this manual page were written by
.An Dag-Erling Sm\(/orgrav Aq Mt des@des.no .