strxfrm - Transform a string

Definition	#include <string.h> size_t strxfrm(char *s1, const char *s2, size_t n); strxfrm transforms the characters in string s2 so that the lexical sequence of each character is interpreted according to the LC_COLLATE category of the current locale. A maximum of n transformed characters (including the terminating null byte) are then copied to string s1. If n has the value 0 then result string s1 can be a NULL pointer. A comparison of two strings transformed with strxfrm using the strcmp function will then return the same result as a comparison with the strcoll function applied to the same original strings.
Return val.	Length of the transformed string (excluding the terminating null byte).
Notes	A string terminated with the null byte (\0) is expected as argument s2. String s2 is not modified by strxfrm. The transformation is performed in a work area. If the return value is greater than or equal to n, the contents of string s1 are indeterminate because no null byte was written. If the hexadecimal value 0 has been assigned to one of the characters in string s2 in the current locale, then this character terminates the transformed string as the null byte (see also section “User-specific locales”). The behavior is undefined if memory areas overlap. The locale concept is described in detail in chapter “Locale”.
Example	#include <stdio.h> #include <string.h> #include <locale.h> int main(void) {   char alpha2[11];   char num2[11];   int comp1;   int comp2;   int comp3;   size_t i = 11;   char *alpha1 = "ABCDEFGHIJ";   char *num1 = "0123456789";   setlocale(LC_COLLATE, "ANNE");       /* Activate the user-specific                                           locale, in which digits have                                           a lower sorting value than                                           letters */   comp1 = strcoll(alpha1, num1);       /* Compare the original strings */   if(comp1 > 0)                        /* using strcoll */      printf ("alpha1 greater than num1\n");   else printf("Fehler\n");   comp2 = strcmp(alpha1, num1);        /* Compare the original strings */   if(comp2 < 0)                        /* using strcmp */      printf ("alpha1 less than num1\n");   else printf("Error\n");   strxfrm(num2, num1, i);              /* Transform with strxfrm */   strxfrm(alpha2, alpha1, i);   comp3 = strcmp(alpha2, num2);        /* Compare the transformed */   if(comp3 > 0)                        /* result strings using strcmp */      printf ("alpha2 greater than num2\n");   else printf("Error\n");   return 0;   }
See also	setlocale, strcoll, strcmp