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diff --git a/man/man3/rand.html b/man/man3/rand.html deleted file mode 100644 index 0601c6bf..00000000 --- a/man/man3/rand.html +++ /dev/null @@ -1,190 +0,0 @@ -<head> -<title>rand(3) - Plan 9 from User Space</title> -<meta content="text/html; charset=utf-8" http-equiv=Content-Type> -</head> -<body bgcolor=#ffffff> -<table border=0 cellpadding=0 cellspacing=0 width=100%> -<tr height=10><td> -<tr><td width=20><td> -<tr><td width=20><td><b>RAND(3)</b><td align=right><b>RAND(3)</b> -<tr><td width=20><td colspan=2> - <br> -<p><font size=+1><b>NAME </b></font><br> - -<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> - - rand, lrand, frand, nrand, lnrand, srand, truerand, ntruerand, - fastrand, nfastrand – random number generator<br> - -</table> -<p><font size=+1><b>SYNOPSIS </b></font><br> - -<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> - - <tt><font size=+1>#include <u.h><br> - #include <libc.h> - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - </font></tt> - <tt><font size=+1>int rand(void) - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - </font></tt> - <tt><font size=+1>long lrand(void) - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - </font></tt> - <tt><font size=+1>double frand(void) - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - </font></tt> - <tt><font size=+1>int nrand(int val) - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - </font></tt> - <tt><font size=+1>long lnrand(long val) - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - </font></tt> - <tt><font size=+1>void srand(long seed) - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - </font></tt> - <tt><font size=+1>ulong truerand(void) - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - </font></tt> - <tt><font size=+1>ulong ntruerand(ulong val)<br> - #include <mp.h><br> - #include <libsec.h> - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - </font></tt> - <tt><font size=+1>void genrandom(uchar *buf, int nbytes) - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - </font></tt> - <tt><font size=+1>void prng(uchar *buf, int nbytes) - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - </font></tt> - <tt><font size=+1>ulong fastrand(void) - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - </font></tt> - <tt><font size=+1>ulong nfastrand(ulong val)<br> - </font></tt> -</table> -<p><font size=+1><b>DESCRIPTION </b></font><br> - -<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> - - <i>Rand</i> returns a uniform pseudo-random number <i>x</i>, 0≤<i>x</i><215. - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - - <i>Lrand</i> returns a uniform <tt><font size=+1>long</font></tt> <i>x</i>, 0≤<i>x</i><231. - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - - <i>Frand</i> returns a uniform <tt><font size=+1>double</font></tt> <i>x</i>, 0.0≤<i>x</i><1.0, This function calls - <i>lrand</i> twice to generate a number with as many as 62 significant - bits of mantissa. - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - - <i>Nrand</i> returns a uniform integer <i>x</i>, 0≤<i>x</i><<i>val. Lnrand</i> is the same, - but returns a <tt><font size=+1>long</font></tt>. - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - - The algorithm is additive feedback with:<br> - - <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> - - x[n] = (x[n-273] + x[n-607]) mod 231 - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - - - </table> - giving a period of 230 × (2607 – 1). - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - - The generators are initialized by calling <i>srand</i> with whatever - you like as argument. To get a different starting value each time,<br> - - <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> - - <tt><font size=+1>srand(time(0)) - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - </font></tt> - - </table> - will work as long as it is not called more often than once per - second. Calling<br> - - <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> - - <tt><font size=+1>srand(1) - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - </font></tt> - - </table> - will initialize the generators to their starting state. - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - - <i>Truerand</i> returns a random unsigned long read from <tt><font size=+1>/dev/random</font></tt>. - Due to the nature of <tt><font size=+1>/dev/random</font></tt>, truerand can only return a few - hundred bits a second. - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - - <i>Ntruerand</i> returns a uniform random integer <i>x</i>, 0≤<i>x</i><<i>val</i>≤<i>232-1. - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - </i> - <i>Genrandom</i> fills a buffer with bytes from the X9.17 pseudo-random - number generator. The X9.17 generator is seeded by 24 truly random - bytes read from <tt><font size=+1>/dev/random</font></tt>. - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - - <i>Prng</i> uses the native <a href="../man3/rand.html"><i>rand</i>(3)</a> pseudo-random number generator to - fill the buffer. Used with <i>srand</i>, this function can produce a - reproducible stream of pseudo random numbers useful in testing. - - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - - Both <i>genrandom</i> and <i>prng</i> may be passed to <i>mprand</i> (see <a href="../man3/mp.html"><i>mp</i>(3)</a>). - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - - <i>Fastrand</i> uses <i>genrandom</i> to return a uniform <tt><font size=+1>unsigned long</font></tt> <i>x</i>, 0≤<i>x</i><<i>232-1. - - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - </i> - <i>Nfastrand</i> uses <i>genrandom</i> to return a uniform <tt><font size=+1>unsigned long</font></tt> <i>x</i>, - 0≤<i>x</i><<i>val</i>≤<i>232-1.<br> - </i> -</table> -<p><font size=+1><b>SOURCE </b></font><br> - -<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> - - <tt><font size=+1>/usr/local/plan9/src/lib9<br> - /usr/local/plan9/src/libsec/port<br> - </font></tt> -</table> -<p><font size=+1><b>SEE ALSO </b></font><br> - -<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> - - <a href="../man3/mp.html"><i>mp</i>(3)</a><br> - -</table> -<p><font size=+1><b>BUGS </b></font><br> - -<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> - - <i>Truerand</i> and <i>ntruerand</i> maintain a static file descriptor. - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - - To avoid name conflicts with the underlying system, <i>rand</i>, <i>lrand</i>, - <i>frand</i>, <i>nrand</i>, <i>lnrand</i>, and <i>srand</i> are preprocessor macros defined - as <i>p9rand</i>, <i>p9lrand</i>, and so on; see <a href="../man3/intro.html"><i>intro</i>(3)</a>.<br> - -</table> - -<td width=20> -<tr height=20><td> -</table> -<!-- TRAILER --> -<table border=0 cellpadding=0 cellspacing=0 width=100%> -<tr height=15><td width=10><td><td width=10> -<tr><td><td> -<center> -<a href="../../"><img src="../../dist/spaceglenda100.png" alt="Space Glenda" border=1></a> -</center> -</table> -<!-- TRAILER --> -</body></html> |