diff --git a/src/files.c b/src/files.c
index acb9d9c..71796d9 100644
--- a/src/files.c
+++ b/src/files.c
@@ -12,7 +12,9 @@ int inputPrimes(char *file, List *list) {
 	if(pFile == NULL) return 1;
 	mpz_t n;
 	mpz_init(n);
-	while(mpz_inp_raw(n, pFile) != 0) addToList(list, n);
+	while(mpz_inp_raw(n, pFile) != 0) {
+		if(addToList(list, n) == 1) return 3;
+	}
 	if(fclose(pFile) != 0) return 2;
 	return 0;
 }
diff --git a/src/files.h b/src/files.h
index ded15bc..f89c48d 100644
--- a/src/files.h
+++ b/src/files.h
@@ -12,7 +12,8 @@
  * @param file File to input primes from.
  * @param list List to load primes into.
  * @returns If 0 then load was successful, if 1 then failed to open,
- * if 2 failed to close.
+ * if 2 failed to close, if 3 failed to allocate new memory to List
+ * (see `addToList()')
  */
 int inputPrimes(char *file, List *list);
 
diff --git a/src/list.c b/src/list.c
index 58c6bac..d8e05df 100644
--- a/src/list.c
+++ b/src/list.c
@@ -7,14 +7,12 @@
  */
 #define BLOCK_SIZE 1024
 
-void initList(List *restrict l) {
+int initList(List *restrict l) {
 	l->list = malloc(sizeof(mpz_t) * BLOCK_SIZE);
-	if(!l->list) {
-		fprintf(stderr, "Failed to allocate memory to list!\n");
-		exit(1);
-	}
+	if(!l->list) return 1;
 	l->size = BLOCK_SIZE;
 	l->end = 0;
+	return 0;
 }
 
 void deInitList(List *restrict l) {
@@ -24,16 +22,14 @@ void deInitList(List *restrict l) {
 	free(l->list);
 }
 
-void addToList(List *l, mpz_t n) {
+int addToList(List *restrict l, mpz_t n) {
 	if(l->end == l->size) {
 		l->size += BLOCK_SIZE;
 		void *tmp = realloc(l->list, sizeof(mpz_t) * l->size);
-		if(!tmp) {
-			fprintf(stderr, "Failed to allocate more memory to list!\n");
-			exit(1);
-		}
+		if(!tmp) return 1;
 		l->list = tmp;
 	}
 	mpz_init(l->list[l->end]);
 	mpz_set(l->list[l->end++], n);
+	return 0;
 }
diff --git a/src/list.h b/src/list.h
index 77b5506..b600654 100644
--- a/src/list.h
+++ b/src/list.h
@@ -23,8 +23,9 @@ typedef struct {
  * @details Initialize the list and its variables, allocating memory
  * to the pointer array inside.
  * @param[in] l A pointer to a List type to be initialized.
+ * @returns Returns 0 if successful and 1 if failed.
  */
-void initList(List *restrict l);
+int initList(List *restrict l);
 
 /**
  * @brief Deinitialize a List.
@@ -38,5 +39,6 @@ void deInitList(List *restrict l);
  * @details Add item `n' at the end of a List type.
  * @param[out] l List to which the variable should be appended.
  * @param[in] n variable to be appended to the list.
+ * @returns Returns 0 if successful and 1 if failed.
  */
-void addToList(List *l, mpz_t n);
+int addToList(List *restrict l, mpz_t n);
diff --git a/src/main.c b/src/main.c
index 6722785..467e9fb 100644
--- a/src/main.c
+++ b/src/main.c
@@ -45,7 +45,7 @@ int main(int argc, char *argv[]) {
 					fprintf(stderr,
 							"Invalid base `%d'. Base must be between 2 and 62.\n",
 							base);
-					exit(1);
+					return 1;
 				}
 				break;
 			case 'f':
@@ -93,7 +93,10 @@ int main(int argc, char *argv[]) {
 
 	// Primes we've found
 	List primes;
-	initList(&primes);
+	if(initList(&primes) == 1) {
+		fprintf(stderr, "Failed to initialize primes list.\n");
+		exit(1);
+	}
 
 	// The number we're going to be testing for
 	mpz_t num;
@@ -108,13 +111,13 @@ int main(int argc, char *argv[]) {
 	if(newFile) {
 		// Add 2, a known prime to this list
 		mpz_set_ui(num, 2);
-		addToList(&primes, num);
+		if(addToList(&primes, num) == 1) {
+			fprintf(stderr, "Failed to allocate more memory for list.\n");
+			goto releaseMemory;
+		}
 		if(!f_quiet) {
-			if(mpz_out_str(stdout, base, num) == 0) {
+			if(mpz_out_str(stdout, base, num) == 0)
 				fprintf(stderr, "Could not print to `stdout'!\n");
-				exitCode = 1;
-				goto releaseMemory;
-			}
 			printf("\n");
 		}
 		mpz_add_ui(num, num, 1);
@@ -129,6 +132,8 @@ int main(int argc, char *argv[]) {
 				fprintf(stderr, "Failed to open Indivisible file `%s'.\n", file);
 			else if(err == 2)
 				fprintf(stderr, "Failed to close Indivisible file `%s'.\n", file);
+			else if(err == 3)
+				fprintf(stderr, "Failed to allocate more memory for list.\n");
 			exitCode = 1;
 			goto releaseMemory;
 		}
@@ -170,13 +175,13 @@ int main(int argc, char *argv[]) {
 		}
 
 		// `num' is a prime so we add it to the list and print it
-		addToList(&primes, num);
+		if(addToList(&primes, num) == 1) {
+			fprintf(stderr, "Failed to allocate more memory for list.\n");
+			goto releaseMemory;
+		}
 		if(!f_quiet) {
-			if(mpz_out_str(stdout, base, num) == 0) {
+			if(mpz_out_str(stdout, base, num) == 0)
 				fprintf(stderr, "Could not print to `stdout'!\n");
-				exitCode = 1;
-				goto releaseMemory;
-			}
 			printf("\n");
 		}