C Programming

FURTHER IMPROVEMENTS by using POINTERS
The previous program still required the use of variables to keep track of string lengths. Implementing concatenation by the use of pointers eliminates this, eg,


	#include <stdio.h>

	void concat( char *, char *, char * );

	/* this functions copies the strings a and b to the destination string c */
	void concat( char *a, char *b, char *c)
	{
		while( *a )  {           /* while( *c++ = *a++ );  */
			*c = *a; ++a; ++c;
		}
		while( *b )  {
			*c = *b; ++b; ++c;
		}
		*c = '\0';
	}

	main()    
	{
		static char string1[] = "Bye Bye ";
		static char string2[] = "love.";
		char string3[20];

		concat( string1, string2, string3);
		printf("%s\n", string3);
	}


USING strcat IN THE LIBRARY ROUTINE string.h
The following program illustrates using the supplied function resident in the appropriate library file. strcat() concatenates one string onto another and returns a pointer to the concatenated string.


	#include <string.h>  
	#include <stdio.h>

	main()
	{
		static char string1[] = "Bye Bye ";
		static char string2[] = "love.";
		char *string3;

		string3 = strcat ( string1, string2 );
		printf("%s\n", string3);
	}


ęCopyright B Brown. 1984-1999. All rights reserved.