C Language Strings Copy and Concatenation: strcpy(), strcat()
Example
#include <stdio.h>
#include <string.h>
int main(void)
{
/* Always ensure that your string is large enough to contain the characters
* and a terminating NUL character ('\0')!
*/
char mystring[10];
/* Copy "foo" into `mystring`, until a NUL character is encountered. */
strcpy(mystring, "foo");
printf("%s\n", mystring);
/* At this point, we used 4 chars of `mystring`, the 3 characters of "foo",
* and the NUL terminating byte.
*/
/* Append "bar" to `mystring`. */
strcat(mystring, "bar");
printf("%s\n", mystring);
/* We now use 7 characters of `mystring`: "foo" requires 3, "bar" requires 3
* and there is a terminating NUL character ('\0') at the end.
*/
/* Copy "bar" into `mystring`, overwriting the former contents. */
strcpy(mystring, "bar");
printf("%s\n", mystring);
return 0;
}
Outputs:
foo
foobar
bar
If you append to or from or copy from an existing string, ensure it is NUL-terminated!
String literals (e.g. "foo") will always be NUL-terminated by the compiler.
