85 lines
2.7 KiB
HTML
85 lines
2.7 KiB
HTML
<!--
|
|
Copyright (c) 2000, 2001, 2002, 2003, 2004, 2005, 2008, 2009, 2013
|
|
The President and Fellows of Harvard College.
|
|
|
|
Redistribution and use in source and binary forms, with or without
|
|
modification, are permitted provided that the following conditions
|
|
are met:
|
|
1. Redistributions of source code must retain the above copyright
|
|
notice, this list of conditions and the following disclaimer.
|
|
2. Redistributions in binary form must reproduce the above copyright
|
|
notice, this list of conditions and the following disclaimer in the
|
|
documentation and/or other materials provided with the distribution.
|
|
3. Neither the name of the University nor the names of its contributors
|
|
may be used to endorse or promote products derived from this software
|
|
without specific prior written permission.
|
|
|
|
THIS SOFTWARE IS PROVIDED BY THE UNIVERSITY AND CONTRIBUTORS ``AS IS'' AND
|
|
ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
ARE DISCLAIMED. IN NO EVENT SHALL THE UNIVERSITY OR CONTRIBUTORS BE LIABLE
|
|
FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
SUCH DAMAGE.
|
|
-->
|
|
<html>
|
|
<head>
|
|
<title>hash</title>
|
|
<link rel="stylesheet" type="text/css" media="all" href="../man.css">
|
|
</head>
|
|
<body bgcolor=#ffffff>
|
|
<h2 align=center>hash</h2>
|
|
<h4 align=center>OS/161 Reference Manual</h4>
|
|
|
|
<h3>Name</h3>
|
|
<p>
|
|
hash - compute a simple hash function of a file
|
|
</p>
|
|
|
|
<h3>Synopsis</h3>
|
|
<p>
|
|
<tt>/testbin/hash</tt> <em>file</em><br>
|
|
<tt>host-hash</tt> <em>file</em>
|
|
</p>
|
|
|
|
<h3>Description</h3>
|
|
<p>
|
|
<tt>hash</tt> takes a file and computes a hash value for it by adding
|
|
all the bytes in the file together modulo a prime.
|
|
</p>
|
|
|
|
<p>
|
|
<tt>hash</tt> is by default also compiled for the System/161 host OS
|
|
so you can cross-check the answers you get.
|
|
</p>
|
|
|
|
<h3>Requirements</h3>
|
|
<p>
|
|
<tt>hash</tt> uses the following system calls:
|
|
<ul>
|
|
<li> <A HREF=../syscall/open.html>open</A>
|
|
<li> <A HREF=../syscall/read.html>read</A>
|
|
<li> <A HREF=../syscall/write.html>write</A>
|
|
<li> <A HREF=../syscall/close.html>close</A>
|
|
<li> <A HREF=../syscall/_exit.html>_exit</A>
|
|
</ul>
|
|
</p>
|
|
|
|
<p>
|
|
Once the basic system calls are complete, hash should work on any file
|
|
the system supports. However, it will probably of most use for testing
|
|
while working on the file system.
|
|
</p>
|
|
|
|
<h3>Bugs</h3>
|
|
<p>
|
|
<tt>hash</tt> uses a silly hash algorithm.
|
|
</p>
|
|
|
|
</body>
|
|
</html>
|