String Handling Functions

Since strings in C are just null-terminated character arrays, you cannot manipulate them directly with operators like `+` for concatenation or `==` for comparison. Instead, C provides a rich set of functions in the standard library header `<string.h>` for performing these operations. Mastering these functions is essential for any C programmer. One of the most basic functions is `strlen(str)`, which returns the length of the string `str`. It counts the number of characters up to, but not including, the null terminator (`'\0'`). For copying strings, you use `strcpy(dest, src)`. This function copies the content of the source string `src` into the destination character array `dest`. It's crucial to ensure that the destination array is large enough to hold the source string, including its null terminator, to avoid buffer overflows. To concatenate (join) two strings, you use `strcat(dest, src)`. This appends the `src` string to the end of the `dest` string. Again, the `dest` array must have enough space for the combined result. For comparing two strings, you use `strcmp(str1, str2)`. This function compares the two strings lexicographically (like in a dictionary). It returns 0 if the strings are identical, a negative value if `str1` comes before `str2`, and a positive value if `str1` comes after `str2`. These are just a few of the most common functions; the `<string.h>` library offers many more for searching, tokenizing, and manipulating strings.