.\"-
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.\" Copyright (c) 2016 Dag-Erling Smørgrav
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.Dd September 17, 2016
.Dt CRYB_PEARSON_HASH 3
.Os
.Sh NAME
.Nm cryb_pearson_hash ,
.Nm cryb_pearson_hash_str
.Nd hash functions
.Sh LIBRARY
.Lb libcryb-hash
.Sh SYNOPSIS
.In stddef.h
.In stdint.h
.In cryb/hash.h
.Ft uint8_t
.Fn cryb_pearson_hash "const void *data" "size_t len"
.Ft uint8_t
.Fn cryb_pearson_hash_str "const char *str"
.Sh DESCRIPTION
The
.Fn cryb_pearson_hash
function returns an 8-bit hash of the
.Va len
first bytes of the object pointed to by
.Va data .
.Pp
The
.Fn cryb_pearson_hash_str
function returns an 8-bit hash of the NUL-terminated string pointed to
by
.Va str ,
not including the terminating NUL.
It is equivalent to calling
.Li cryb_pearson_hash(str, strlen(str)) .
.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 STANDARDS
.Rs
.%A "Pearson, Peter K."
.%D "June 1990"
.%T "Fast Hashing of Variable-Length Text Strings"
.%J "Communications of the ACM"
.%V "33"
.%N "6"
.%P "677"
.%O "doi:10.1145/78973.78978"
.Re
.Sh AUTHORS
The
.Fn cryb_pearson_hash
and
.Fn cryb_pearson_hash_str
functions and this manual page were written for the University of Oslo by
.An Dag-Erling Sm\(/orgrav Aq Mt d.e.smorgrav@usit.uio.no .