string.h File Reference

#include <stdarg.h>
#include <types.h>

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Functions
void *	memcpy (void *dst, const void *src, int cnt) __attribute__((optimize("O0")))
	Copies the values of 'cnt' bytes from memory area 'src' to memory area 'dst'.
void *	memset (void *dst, int val, int cnt) __attribute__((optimize("O0")))
	Sets the first 'cnt' bytes of the memory area pointed to by 'dst' to the specified value 'val'.
int	memcmp (const void *dst, const void *src, unsigned int cnt) __attribute__((optimize("O0")))
	Compares the first 'cnt' bytes of the memory areas 'dst' and 'src'.
unsigned int	strlen (const char *str) __attribute__((optimize("O0")))
	Calculates the length of the string 'str', excluding the terminating null byte.
unsigned int	strnlen (const char *s, unsigned int n) __attribute__((optimize("O0")))
	Calculates the length of the string 's', but not more than 'n' characters.
char *	strcpy (char *dst, const char *src) __attribute__((optimize("O0")))
	Copies the string pointed to by 'src', including the terminating null byte, to the buffer pointed to by 'dst'.
char *	strncpy (char *dest, const char *src, unsigned int n) __attribute__((optimize("O0")))
	Copies up to 'n' characters from the string pointed to by 'src', including the terminating null byte, to the buffer pointed to by 'dest'.
char *	strcat (char *dst, const char *src) __attribute__((optimize("O0")))
	Appends the string pointed to by 'src', including the terminating null byte, to the end of the string pointed to by 'dst'.
int	strcmp (const char *p1, const char *p2) __attribute__((optimize("O0")))
	Compares the string pointed to by 'p1' to the string pointed to by 'p2'.
int	strncmp (const char *p1, const char *p2, unsigned int cnt) __attribute__((optimize("O0")))
	Compares at most the first 'cnt' characters of the string pointed to by 'p1' to the string pointed to by 'p2'.
char *	strchr (const char *s, int c) __attribute__((optimize("O0")))
	Finds the first occurrence of the character 'c' (converted to a char) in the string pointed to by 's', including the terminating null byte.
char *	strrchr (const char *s, int c) __attribute__((optimize("O0")))
	Finds the last occurrence of the character 'c' (converted to a char) in the string pointed to by 's', including the terminating null byte.
char *	strstr (const char *s, const char *what) __attribute__((optimize("O0")))
	Finds the first occurrence of the substring 'what' in the string 's'.
void *	memchr (void *ptr, int value, unsigned int num) __attribute__((optimize("O0")))
	Locates the first occurrence of the character 'value' (converted to an unsigned char) in the first 'num' bytes of the memory area pointed to by 'ptr'.
void *	memmove (void *dest, const void *src, unsigned int count) __attribute__((optimize("O0")))
	Copies 'count' bytes from the memory area 'src' to the memory area 'dest'.

Function Documentation

memchr()

void * memchr	(	void *	ptr,
		int	value,
		unsigned int	num
	)

Locates the first occurrence of the character 'value' (converted to an unsigned char) in the first 'num' bytes of the memory area pointed to by 'ptr'.

Parameters

ptr	The input memory area.
value	The value to search for.
num	The number of bytes to examine.

Returns

A pointer to the located character, or NULL if the character does not occur in the memory area.

memcmp()

int memcmp	(	const void *	dst,
		const void *	src,
		unsigned int	cnt
	)

Compares the first 'cnt' bytes of the memory areas 'dst' and 'src'.

Parameters

dst	The first memory area to compare.
src	The second memory area to compare.
cnt	The number of bytes to compare.

Returns

An integer less than, equal to, or greater than zero if 'dst' is found, respectively, to be less than, to match, or be greater than 'src'.

memcpy()

void * memcpy	(	void *	dst,
		const void *	src,
		int	cnt
	)

Copies the values of 'cnt' bytes from memory area 'src' to memory area 'dst'.

Parameters

dst	The destination memory area.
src	The source memory area.
cnt	The number of bytes to copy.

Returns

A pointer to the destination memory area.

memmove()

void * memmove	(	void *	dest,
		const void *	src,
		unsigned int	count
	)

Copies 'count' bytes from the memory area 'src' to the memory area 'dest'.

The memory areas may overlap.

Parameters

dest	The destination memory area.
src	The source memory area.
count	The number of bytes to copy.

Returns

A pointer to the destination memory area.

memset()

void * memset	(	void *	dst,
		int	val,
		int	cnt
	)

Sets the first 'cnt' bytes of the memory area pointed to by 'dst' to the specified value 'val'.

Parameters

dst	The memory area to be filled.
val	The value to be set.
cnt	The number of bytes to be set to the value.

Returns

A pointer to the destination memory area.

strcat()

char * strcat	(	char *	dst,
		const char *	src
	)

Appends the string pointed to by 'src', including the terminating null byte, to the end of the string pointed to by 'dst'.

Parameters

dst	The destination string.
src	The source string.

Returns

A pointer to the destination string.

strchr()

char * strchr	(	const char *	s,
		int	c
	)

Finds the first occurrence of the character 'c' (converted to a char) in the string pointed to by 's', including the terminating null byte.

Parameters

s	The input string.
c	The character to search for.

Returns

A pointer to the located character, or NULL if the character does not occur in the string.

strcmp()

int strcmp	(	const char *	p1,
		const char *	p2
	)

Compares the string pointed to by 'p1' to the string pointed to by 'p2'.

Parameters

p1	The first string to compare.
p2	The second string to compare.

Returns

An integer less than, equal to, or greater than zero if 'p1' is found, respectively, to be less than, to match, or be greater than 'p2'.

strcpy()

char * strcpy	(	char *	dst,
		const char *	src
	)

Copies the string pointed to by 'src', including the terminating null byte, to the buffer pointed to by 'dst'.

Parameters

dst	The destination buffer.
src	The source string.

Returns

A pointer to the destination buffer.

strlen()

unsigned int strlen

(

const char *

str

)

Calculates the length of the string 'str', excluding the terminating null byte.

Parameters

str	The input string.

Returns

The length of the input string.

strncmp()

int strncmp	(	const char *	p1,
		const char *	p2,
		unsigned int	cnt
	)

Compares at most the first 'cnt' characters of the string pointed to by 'p1' to the string pointed to by 'p2'.

Parameters

p1	The first string to compare.
p2	The second string to compare.
cnt	The maximum number of characters to compare.

Returns

An integer less than, equal to, or greater than zero if 'p1' is found, respectively, to be less than, to match, or be greater than 'p2'.

strncpy()

char * strncpy	(	char *	dest,
		const char *	src,
		unsigned int	n
	)

Copies up to 'n' characters from the string pointed to by 'src', including the terminating null byte, to the buffer pointed to by 'dest'.

Parameters

dest	The destination buffer.
src	The source string.
n	The maximum number of characters to be copied.

Returns

A pointer to the destination buffer.

strnlen()

unsigned int strnlen	(	const char *	s,
		unsigned int	n
	)

Calculates the length of the string 's', but not more than 'n' characters.

Parameters

s	The input string.
n	The maximum number of characters to examine.

Returns

The length of the input string, but not more than 'n'.

strrchr()

char * strrchr	(	const char *	s,
		int	c
	)

Finds the last occurrence of the character 'c' (converted to a char) in the string pointed to by 's', including the terminating null byte.

Parameters

s	The input string.
c	The character to search for.

Returns

A pointer to the located character, or NULL if the character does not occur in the string.

strstr()

char * strstr	(	const char *	s,
		const char *	what
	)

Finds the first occurrence of the substring 'what' in the string 's'.

Parameters

s	The input string.
what	The substring to search for.

Returns

A pointer to the beginning of the located substring, or NULL if the substring does not occur in the string.