an assortment of C

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#define LINE_SIZE 10000

/**
 * Reads doubles from in until EOF.
 * If le n is not null, *len is set to
 * the number of elements read.
 * The caller is responsible for freeing the 
 * memory of the returned object.
 * Returns null in case of an error.
 */
double* readArray(FILE* in, int* len)
{
  const char* SPACES = " \t\r\n";
  char* line = malloc(LINE_SIZE);
  int capacity = 100;
  double* y = malloc(sizeof(double) * capacity);
  int n = 0;
  while (!ferror(in) && !feof(in)) {
    if (fgets(line, LINE_SIZE, in)) {
      const char* next = line;
      while (*next) {
 next += strspn(next, SPACES);
 if (*next) {
   double v;
   if (sscanf(next, "%lf", &v) == 1) {
     if (capacity == n) {
       capacity *= 2;
       y = realloc(y, capacity * sizeof(double));
     }

     y[n] = v;
     ++n;
   }
   else {
     free(line);
     free(y);
     return 0;
   }
 }
 next += strcspn(next, SPACES);
      }
    }
    else {
      if (!feof(in)) {
 free(line);
 free(y);
 return 0;
      }
    }
  }

  if (len) {
    *len = n;
  }

  return y;
}

/**
 * Reads doubles from file.
 * If len is not null, *len is set to the
 * number of elements read.
 * The caller is responsible for freeing the 
 * memory of the returned object.
 * Returns null in case of an error.
 */
double* readArrayFromFile(const char* file, int* len)
{
  FILE* in = fopen(file, "r");
  double* result = 0;
  if (!in) {
    fprintf(stderr, "Problem opening %s\n", file);
    perror("");
  }
  else {
    result = readArray(in, len);
    fclose(in);
  }
  return result;
}

/**
 * Returns 1 if tail is a suffix of s, 0 otherwise.
 */
int endsWith(const char* s, const char* tail)
{
  const int sLen = strlen(s);
  const int tailLen = strlen(tail);
  if (sLen >= tailLen) {
    return strcmp(s + sLen - tailLen, tail) == 0;
  }
  else {
    return 0;
  }
}

int remove(double* y, const int len,
const double toRemove)
{
  int newLen = 0;
  int i;
  
  for (i = 0; i < len; ++i) {
    const double yi = y[i];
    if (yi != toRemove) {
      y[newLen] = yi;
      ++newLen;
    }
  }
  return newLen;
}