Strings

Strings

• not first class data types in C (like int or float)

• really just character (char) arrays

• have a fixed maximum length

• can and often are indexed like arrays (from 0)

• need ‘terminating’ with an end of string marker (hidden character \0, the ASCII NUL character)

Printing Strings

using %s

• printf("You typed %s\n", answer); 

• Assuming ‘answer’ is either a char array or a pointer to a char 

• char *answer = "hello"; 

• char answer[] = "hello";

Get Strings

 using %s

• char answer[20]; // max length including \0 is 20! 

• scanf("%s", answer);

Comparing Strings

compare the pointers to the locations not the actual data

strcmp()

compares 2 strings and returns -1, 0, 1 (less, equal, greater)

In <string.h>

• int strlen(char *) // find the length of string s

• char strchr(char , int) // find a character within a string (pointer or NULL) 

• strcat(char d, char s) // append string s to d

• strcpy(char d, char s) // copy string s to d