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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML>
<HEAD>
<TITLE>mem.h</TITLE>
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<FONT SIZE="5"><B>The <mem.h> Header File</B></FONT>
<HR>
<P><B>Routines for manipulation of memory blocks</B></P>
<H3><U>Functions</U></H3>
<DL INDENT="20"><DT><B><A HREF="#_memset">_memset</A></B><DD>Sets <I>num</I> bytes of <I>buffer</I> to byte <I>c</I>.<IMG WIDTH="1" HEIGHT="20" ALIGN="TOP"><DT><B><A HREF="#memchr">memchr</A></B><DD>Searches the first <I>len</I> bytes of array <I>str</I> for character <I>c</I>.<IMG WIDTH="1" HEIGHT="20" ALIGN="TOP"><DT><B><A HREF="#memcmp">memcmp</A></B><DD>Compares two blocks of signed chars.<IMG WIDTH="1" HEIGHT="20" ALIGN="TOP"><DT><B><A HREF="#memcpy">memcpy</A></B><DD>Copies a block of <I>len</I> bytes from <I>src</I> to <I>dest</I>.<IMG WIDTH="1" HEIGHT="20" ALIGN="TOP"><DT><B><A HREF="#memmove">memmove</A></B><DD>Copies a block of <I>len</I> bytes from <I>src</I> to <I>dest</I>, with possibility
of overlaping of source and destination block.<IMG WIDTH="1" HEIGHT="20" ALIGN="TOP"><DT><B><A HREF="#memset">memset</A></B><DD>Sets <I>num</I> bytes of <I>buffer</I> to byte <I>c</I>.<IMG WIDTH="1" HEIGHT="20" ALIGN="TOP"><DT><B><A HREF="#memucmp">memucmp</A></B><DD>Compares two blocks of unsigned chars.</DL>
<H3><U>Constants</U></H3>
<DL INDENT="20"><DT><B><A HREF="alloc.html#NULL">NULL</A></B><DD>A null-pointer value.</DL>
<H3><U>Predefined Types</U></H3>
<DL INDENT="20"><DT><B><A HREF="stddef.html#size_t">size_t</A></B><DD>A type to define sizes of strings and memory blocks.</DL>
<P>See also: <A HREF="alloc.html">alloc.h</A></P>
<HR>
<H3><A NAME="_memset"><U>_memset</U></A></H3>
<P><TABLE BORDER="1" CELLPADDING="2"><TR><TD CLASS="CODE"><B><A HREF="keywords.html#void">void</A></B> *_memset (<B><A HREF="keywords.html#void">void</A></B> *buffer, <B><A HREF="keywords.html#short">short</A></B> c, <B><A HREF="keywords.html#short">unsigned</A></B> <B><A HREF="keywords.html#short">long</A></B> num);</TD></TR></TABLE></P>
<P><B>Sets <I>num</I> bytes of <I>buffer</I> to byte <I>c</I>.</B></P>
<P>_memset is a slower (byte-by-byte) variant of
<A HREF="#memset">memset</A>.</P>
<HR>
<H3><A NAME="memchr"><U>memchr</U></A></H3>
<P><TABLE BORDER="1" CELLPADDING="2"><TR><TD CLASS="CODE"><B><A HREF="keywords.html#void">void</A></B> *memchr (<B><A HREF="keywords.html#const">const</A></B> <B><A HREF="keywords.html#void">void</A></B> *str, <B><A HREF="keywords.html#short">short</A></B> c, <B><A HREF="keywords.html#short">unsigned</A></B> <B><A HREF="keywords.html#short">long</A></B> len);</TD></TR></TABLE></P>
<P><B>Searches the first <I>len</I> bytes of array <I>str</I> for character <I>c</I>.</B></P>
<P>memchr searches the first <I>len</I> bytes of the block pointed to by <I>str</I> for
character <I>c</I>. On success, memchr returns a pointer to the first occurrence of
<I>c</I> in <I>str</I>. Otherwise, it returns <A HREF="alloc.html#NULL">NULL</A>.</P>
<HR>
<H3><A NAME="memcmp"><U>memcmp</U></A></H3>
<P><TABLE BORDER="1" CELLPADDING="2"><TR><TD CLASS="CODE"><B><A HREF="keywords.html#short">short</A></B> memcmp (<B><A HREF="keywords.html#const">const</A></B> <B><A HREF="keywords.html#void">void</A></B> *s1, <B><A HREF="keywords.html#const">const</A></B> <B><A HREF="keywords.html#void">void</A></B> *s2, <B><A HREF="keywords.html#short">unsigned</A></B> <B><A HREF="keywords.html#short">long</A></B> len);</TD></TR></TABLE></P>
<P><B>Compares two blocks of signed chars.</B></P>
<P>memcmp compares the first <I>len</I> bytes of the blocks <I>s1</I> and <I>s2</I> as signed chars.
Since it compares bytes as signed chars, memcmp returns a value</P>
<UL>
<LI><P>< 0 if <I>s1</I> is less than <I>s2</I></P></LI>
<LI><P>=0 if <I>s1</I> is the same as <I>s2</I></P></LI>
<LI><P>> 0 if <I>s1</I> is greater than <I>s2</I></P></LI>
</UL>
<P>For example, <CODE>memcmp("\xFF","\x7F",1)</CODE> returns a value greater than 0. More precisely,
the exact return value is the result of subtracting the first pair of values
that differ in the two blocks being compared based on them being signed
chars.
<BR><BR>
<B>Note:</B> This routine is declared as "short" although the ANSI standard proposes "long". This is important,
because the TIOS memcmp routine puts garbage in the higher half of the d0 register.</P>
<P>See also: <A HREF="#memucmp">memucmp</A></P>
<HR>
<H3><A NAME="memcpy"><U>memcpy</U></A></H3>
<P><TABLE BORDER="1" CELLPADDING="2"><TR><TD CLASS="CODE"><B><A HREF="keywords.html#void">void</A></B> *memcpy (<B><A HREF="keywords.html#void">void</A></B> *dest, <B><A HREF="keywords.html#const">const</A></B> <B><A HREF="keywords.html#void">void</A></B> *src, <B><A HREF="keywords.html#short">unsigned</A></B> <B><A HREF="keywords.html#short">long</A></B> len);</TD></TR></TABLE></P>
<P><B>Copies a block of <I>len</I> bytes from <I>src</I> to <I>dest</I>.</B></P>
<P>memcpy copies a block of <I>len</I> bytes from <I>src</I> to <I>dest</I>.
If <I>src</I> and <I>dest</I> overlap,
the memcpy is ill-behaved (in such case, use <A HREF="#memmove">memmove</A> instead).
memcpy returns <I>dest</I>.</P>
<HR>
<H3><A NAME="memmove"><U>memmove</U></A></H3>
<P><TABLE BORDER="1" CELLPADDING="2"><TR><TD CLASS="CODE"><B><A HREF="keywords.html#void">void</A></B> *memmove (<B><A HREF="keywords.html#void">void</A></B> *dest, <B><A HREF="keywords.html#const">const</A></B> <B><A HREF="keywords.html#void">void</A></B> *src, <B><A HREF="keywords.html#short">unsigned</A></B> <B><A HREF="keywords.html#short">long</A></B> len);</TD></TR></TABLE></P>
<P><B>Copies a block of <I>len</I> bytes from <I>src</I> to <I>dest</I>, with possibility
of overlaping of source and destination block.</B></P>
<P>memmove copies a block of <I>len</I> bytes from <I>src</I> to <I>dest</I>.
Even when the source and destination blocks overlap, bytes in the overlapping
locations are copied
correctly (in opposite to <A HREF="#memcpy">memcpy</A>). memmove returns <I>dest</I>.</P>
<HR>
<H3><A NAME="memset"><U>memset</U></A></H3>
<P><TABLE BORDER="1" CELLPADDING="2"><TR><TD CLASS="CODE"><B><A HREF="keywords.html#void">void</A></B> *memset (<B><A HREF="keywords.html#void">void</A></B> *buffer, <B><A HREF="keywords.html#short">short</A></B> c, <B><A HREF="keywords.html#short">unsigned</A></B> <B><A HREF="keywords.html#short">long</A></B> num);</TD></TR></TABLE></P>
<P><B>Sets <I>num</I> bytes of <I>buffer</I> to byte <I>c</I>.</B></P>
<P>memset sets the first <I>num</I> bytes of the array <I>buffer</I> to the character <I>c</I>.
memset is faster than _<A HREF="#_memset">memset</A>, because it sets a
memory in a 4-byte chunks as long as possible. memset returns <I>buffer</I>.</P>
<HR>
<H3><A NAME="memucmp"><U>memucmp</U></A></H3>
<P><A HREF="httigcc.html#minams">AMS 2.00 or higher</A></P>
<P><TABLE BORDER="1" CELLPADDING="2"><TR><TD CLASS="CODE"><B><A HREF="keywords.html#short">short</A></B> memucmp (<B><A HREF="keywords.html#const">const</A></B> <B><A HREF="keywords.html#void">void</A></B> *s1, <B><A HREF="keywords.html#const">const</A></B> <B><A HREF="keywords.html#void">void</A></B> *s1, <B><A HREF="keywords.html#short">unsigned</A></B> <B><A HREF="keywords.html#short">long</A></B> len);</TD></TR></TABLE></P>
<P><B>Compares two blocks of unsigned chars.</B></P>
<P>memucmp acts like <A HREF="#memcmp">memcmp</A>, but treats <I>s1</I>
and <I>s2</I> as pointers to unsigned chars.</P>
<P>See also: <A HREF="#memcmp">memcmp</A></P>
<HR>
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