Unix_functions.c

#include "shell.h"
/**
 * *_strcat - concatenates @src to @dest
 * @src: the source string to append to @dest
 * @dest: the destination string to be concatenated upon
 * Return:pointer to the resulting string.
 */
char *_strcat(char *dest, char *src)
{
	int index = 0, dest_len = 0;

	if (dest == NULL || src == NULL)
		return (dest);

	while (dest[index++])
		dest_len++;
	for (index = 0; src[index]; index++)

		dest[dest_len++] = src[index];

	dest[dest_len] = '\0';
	return (dest);
}
/**
 * *_strdup - function copys string to new memory space location
 * @str: char string to copy
 * Return: 0
 */

char *_strdup(char *str)

{

	char *ptr;
	int a, ret = 0;

	if (str == NULL)

		return (NULL);

	a = 0;

	while (str[a] != '\0')
		a++;
	ptr = malloc(sizeof(char) * (a + 1));
	if (ptr == NULL)
		return (NULL);
	for (ret = 0; str[ret] != '\0'; ret++)
		ptr[ret] = str[ret];
	ptr[ret] = '\0';
	return (ptr);
}

/**
 * _strlen - checks the length of a string
 * @s: string to check
 * Return: int length of the string.
 */

int _strlen(char *s)

{
	int length = 0;

	while (s[length])
		length++;
	return (length);
}

/**
 * *_strcpy - function copies the string pointed to by src.
 * @dest: char destination string
 * @src: char source string
 * Description: Copy the string pointed to by pointer __src__ to
 * the buffer pointed to by **dest**
 * Return: Pointer to _dest_
 */

char *_strcpy(char *dest, const char *src)
{
	int n = 0;

	while (src[n] != '\0')
	{
		dest[n] = src[n];
		n++;
	}
	dest[n] = '\0';

	return (dest);
}
/**
 * *_strchr - function searches a string for an integer
 * @str: pointer to string given
 * @ch: integer value to search for
 * Return: if success - pointer to the ineteger character
 * Else: NULL.
 */

char *_strchr(const char *str, int ch)
{
	while (*str != '\0')
	{
		if (*str == ch)
		{
			return ((char *) (str));
		}
		str++;
	}
	if (ch == '\0')
	{
		return ((char *) (str));
	}
	return (NULL);
}