Here is the simplest thing i could think of. Note that this program uses second command line argument (argv[1]) as a line to delete whitespaces from.
#include <string.h>
#include <stdio.h>
#include <stdlib.h>
/*The function itself with debug printing to help you trace through it.*/
char* trim(const char* str)
{
char* res = malloc(sizeof(str) + 1);
char* copy = malloc(sizeof(str) + 1);
copy = strncpy(copy, str, strlen(str) + 1);
int index = 0;
for (int i = 0; i < strlen(copy) + 1; i++) {
if (copy[i] != ' ')
{
res[index] = copy[i];
index++;
}
printf("End of iteration %d\n", i);
printf("Here is the initial line: %s\n", copy);
printf("Here is the resulting line: %s\n", res);
printf("\n");
}
return res;
}
int main(int argc, char* argv[])
{
//trim function test
const char* line = argv[1];
printf("Here is the line: %s\n", line);
char* res = malloc(sizeof(line) + 1);
res = trim(line);
printf("\nAnd here is the formatted line: %s\n", res);
return 0;
}