diff --git a/Makefile b/Makefile
index 3eb018f..e0f92d0 100644
--- a/Makefile
+++ b/Makefile
@@ -8,10 +8,9 @@ PREFIX = /usr/local
 LIBPREFIX = $(PREFIX)/lib
 
 # флегови за C компајлер и линкер
-CPPFLAGS = -D_POSIX_C_SOURCE=200200L -DDESTDIR=\"$(DESTDIR)\" \
--DVERSION=\"$(VERSION)\"
-CFLAGS = -g -std=c99 -pedantic -Wall -O0
-# CFLAGS  = -std=c99 -pedantic -Wall -O3
+CPPFLAGS = -D_POSIX_C_SOURCE=2 -DDESTDIR=\"$(DESTDIR)\" -DVERSION=\"$(VERSION)\"
+# CFLAGS = -g -std=c99 -pedantic -Wall -O0
+CFLAGS  = -std=c99 -pedantic -Wall -O3
 LDFLAGS = -lm -lc
 
 CC = cc
diff --git a/read.c b/read.c
index 1098673..13ba1b0 100644
--- a/read.c
+++ b/read.c
@@ -4,7 +4,6 @@
 #include <wctype.h>
 #include <ctype.h>
 #include <string.h>
-#include <regex.h>
 
 #include "util.h"
 #include "read.h"
@@ -138,12 +137,45 @@ wint_t unscanwc(wint_t c, FILE *stream)
 	}
 }
 
-int lengthDigitArray(char *s)
+int validFracNum(char *s)
 {
-	int i;
-	for (i = 0; isdigit(s[i]); ++i)
-		;
-	return i;
+	char *endptr;
+	strtoll(s, &endptr, 10);
+	if (*endptr == '\0' && endptr != s)
+	{
+		return 1;
+	}
+	else if (*endptr == '/' && endptr != s)
+	{
+		char *denom = endptr + 1;
+		strtoll(denom, &endptr, 10);
+		if (*endptr == '\0' && endptr != denom)
+		{
+			return 1;
+		}
+		else
+		{
+			return 0;
+		}
+	}
+	else
+	{
+		return 0;
+	}
+}
+
+int validRealNum(char *s)
+{
+	char *endptr;
+	strtold(s, &endptr);
+	if (*endptr == '\0')
+	{
+		return 1;
+	}
+	else
+	{
+		return 0;
+	}
 }
 
 object getToken(FILE *stream)
@@ -190,25 +222,17 @@ object getToken(FILE *stream)
 	char *s = malloc(n * sizeof(char));
 	wcstombs(s, buffer, n);
 
-	regex_t regNumberFrac, regNumberReal;
-	regcomp(&regNumberFrac, "^[-+]?[[:digit:]]+(/[[:digit:]]+)?$",
-						REG_EXTENDED);
-	regcomp(&regNumberReal, "^[-+]?[[:digit:]]*,[[:digit:]]+$",
-						REG_EXTENDED);
-	const int nmatches = 1;
-	regmatch_t a[nmatches];
-
-	if (!regexec(&regNumberFrac, s, nmatches, a, 0))
+	char *endptr;
+	if (validFracNum(s))
 	{
 		TYPE(result) = numberObject;
 		NUM_TYPE(result) = fractionNum;
-		NUM_NUMER(result) = atoll(s);
-		char *tmp;
-		NUM_DENOM(result) = (tmp = strchr(s, '/')) == NULL ?
-			1 : atoll(tmp + 1);
+		NUM_NUMER(result) = strtoll(s, &endptr, 10);
+		NUM_DENOM(result) = *endptr == '/' ?
+			strtoll(endptr + 1, &endptr, 10) : 1;
 		result = shortenFractionNum(result);
 	}
-	else if (!regexec(&regNumberReal, s, nmatches, a, 0))
+	else if (validRealNum(s))
 	{
 		TYPE(result) = numberObject;
 		NUM_TYPE(result) = realNum;
@@ -220,8 +244,6 @@ object getToken(FILE *stream)
 		SYM(result) = malloc((strlen(s) + 1) * sizeof(char));
 		strcpy(SYM(result), s);
 	}
-	regfree(&regNumberFrac);
-	regfree(&regNumberReal);
 
 	return result;
 }