Code:
#include <stdio.h>
char *zStrtok(char *str, const char *delim) {
static char *static_str=0; /* var to store last address */
int index=0, strlength=0; /* integers for indexes */
int found = 0; /* check if delim is found */
/* delimiter cannot be NULL
* if no more char left, return NULL as well
*/
if (delim==0 || (str == 0 && static_str == 0))
return 0;
if (str == 0)
str = static_str;
/* get length of string */
while(str[strlength])
strlength++;
/* find the first occurance of delim */
for (index=0;index<strlength;index++)
if (str[index]==delim[0]) {
found=1;
break;
}
/* if delim is not contained in str, return str */
if (!found) {
static_str = 0;
return str;
}
/* check for consecutive delimiters
*if first char is delim, return delim
*/
if (str[0]==delim[0]) {
static_str = (str + 1);
return (char *)delim;
}
/* terminate the string
* this assignmetn requires char[], so str has to
* be char[] rather than *char which will cause SIGSEGV
*/
str[index] = '\0';
/* save the rest of string */
if ((str + index + 1)!=0)
static_str = (str + index + 1);
else
static_str = 0;
return str;
}
int main() {
char s[]="A,B,C,D,E,F,G,H,I";
printf("1 %s\n",zStrtok(s,","));
printf("2 %s\n",zStrtok(NULL,","));
printf("3 %s\n",zStrtok(NULL,","));
printf("4 %s\n",zStrtok(NULL,","));
printf("5 %s\n",zStrtok(NULL,","));
printf("6 %s\n",zStrtok(NULL,","));
printf("7 %s\n",zStrtok(NULL,","));
printf("8 %s\n",zStrtok(NULL,","));
printf("9 %s\n",zStrtok(NULL,","));
printf("10 %s\n",zStrtok(NULL,","));
printf("11 %s\n",zStrtok(NULL,","));
printf("12 %s\n",zStrtok(NULL,","));
printf("13 %s\n",zStrtok(NULL,","));
printf("14 %s\n",zStrtok(NULL,","));
return 0;
}
after 10th printf(), it is (null), if static_str[0] is used, program crashes in Win whereas, in linux, I had to add it to evaluate the case.