diff --git a/include/misc.h b/include/misc.h
index c862219..9399d47 100644
--- a/include/misc.h
+++ b/include/misc.h
@@ -5,11 +5,11 @@
 
 #include <why2/flags.h>
 
-int checkVersion(inputFlags flags); //THIS FUNCTION CHECKS IF LATEST VERSION OF WHY2 IS USED
 void generateTextKeyChain(char *key, int *textKeyChain, int textKeyChainSize); //GENERATES ARRAY FOR ENCRYPTION/DECRYPTION
 void deallocateOutput(outputFlags flags); //DEALLOCATES flags
-void checkKey(char *key, inputFlags flags); //CHECKS IF KEY IS VALID
-void checkText(char *text, inputFlags flags); //CHECKS IF TEXT IS VALID
+int checkVersion(inputFlags flags); //THIS FUNCTION CHECKS IF LATEST VERSION OF WHY2 IS USED
+int checkKey(char *key, inputFlags flags); //CHECKS IF KEY IS VALID
+int checkText(char *text, inputFlags flags); //CHECKS IF TEXT IS VALID
 unsigned long countIntLength(int number); //RETURNS LENGTH OF number
 unsigned long countUnusedKeySize(char *text, char *key); //COUNT unusedKeySize
 unsigned long compareTimeMicro(struct timeval startTime, struct timeval finishTime); //COMPARE TIMES IN MICROSECONDS
diff --git a/src/lib/misc.c b/src/lib/misc.c
index 3e751d8..2f651e8 100644
--- a/src/lib/misc.c
+++ b/src/lib/misc.c
@@ -287,21 +287,21 @@ void deallocateOutput(outputFlags flags)
     free(flags.usedKey);
 }
 
-void checkKey(char *key, inputFlags flags)
+int checkKey(char *key, inputFlags flags)
 {
     if (strlen(key) < getKeyLength())
     {
         if (!flags.noOutput) fprintf(stderr, "Key must be at least %lu characters long!\n", getKeyLength());
-        return noOutput(INVALID_KEY);
+        return INVALID_KEY;
     }
 }
 
-void checkText(char *text, inputFlags flags)
+int checkText(char *text, inputFlags flags)
 {
     if (strcmp(text, "") == 0)
     {
         if (!flags.noOutput) fprintf(stderr, "No text to encrypt!\n");
-        return noOutput(INVALID_TEXT);
+        return INVALID_TEXT;
     }
 }