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+.TH MEMORY 10.2
+.SH NAME
+memccpy, memchr, memcmp, memcpy, memmove, memset \- memory operations
+.SH SYNOPSIS
+.ta \w'\fLvoid* 'u
+.B
+void* memccpy(void *s1, void *s2, int c, long n)
+.PP
+.B
+void* memchr(void *s, int c, long n)
+.PP
+.B
+int memcmp(void *s1, void *s2, long n)
+.PP
+.B
+void* memcpy(void *s1, void *s2, long n)
+.PP
+.B
+void* memmove(void *s1, void *s2, long n)
+.PP
+.B
+void* memset(void *s, int c, long n)
+.SH DESCRIPTION
+These functions operate efficiently on memory areas
+(arrays of bytes bounded by a count, not terminated by a zero byte).
+They do not check for the overflow of any receiving memory area.
+.PP
+.I Memccpy
+copies bytes from memory area
+.I s2
+into
+.IR s1 ,
+stopping after the first occurrence of byte
+.I c
+has been copied, or after
+.I n
+bytes have been copied, whichever comes first.
+It returns a pointer to the byte after
+the copy of
+.I c
+in
+.IR s1 ,
+or zero if
+.I c
+was not found in the first
+.I n
+bytes of
+.IR s2 .
+.PP
+.I Memchr
+returns a pointer to the first
+occurrence of byte
+.I c
+in the first
+.I n
+bytes of memory area
+.IR s,
+or zero if
+.I c
+does not occur.
+.PP
+.I Memcmp
+compares its arguments, looking at the first
+.I n
+bytes only, and returns an integer
+less than, equal to, or greater than 0,
+according as
+.I s1
+is lexicographically less than, equal to, or
+greater than
+.IR s2 .
+The comparison is bytewise unsigned.
+.PP
+.I Memmove
+copies
+.I n
+bytes from memory area
+.I s2
+to
+.IR s1 .
+It returns
+.IR s1 .
+It is guaranteed to work if
+.I s1
+and
+.IR s2
+overlap.
+.PP
+In the Inferno kernel
+.I memcpy
+is equivalent to
+.IR memmove .
+(In ANSI C, by contrast,
+.I memcpy
+does not account for overlapping memory regions.)
+.PP
+.I Memset
+sets the first
+.I n
+bytes in memory area
+.I s
+to the value of the least significant byte of
+.IR c .
+It returns
+.IR s .
+.SH DIAGNOSTICS
+If
+.I memcpy
+and
+.I memmove
+are handed negative counts, they abort.
+.SH SOURCE
+.BR /libkern/mem*.c
+.br
+.BR /libkern/mem*-\fIobjtype\fP.s
+.SH SEE ALSO
+.IR strcat (10.2)