Rewrite the string operator function in string. H-strncat

Function prototype: char * strncat (char * DEST, const char * Source, size_t size)

Return Value: returns the pointer to the first address of the target string DeST. If null is returned, an error occurs.

Parameter description:

DeST: string with '/0' as the Terminator

Source: string with '/0' as the ending character

Size: number of characters to connect to the end of the dest

Function: connects the size starting from source to the end of DeST and overwrites '/0' to connect strings.

Implementation:

 

Char * strncat (char * DEST, const char * Source, size_t size)

{
Assert (null! = DEST) & (null! = Source ));
Char * TMP = DEST;
If (size)
{
While (* DEST)
DeST ++;
While (* DEST ++ = * Source ++ ))
{If (-- size = 0)
Break;
}
}
Return TMP;
}