Allow compilation on Darwin

--- netcat.c
+++ netcat.c
@@ -43,11 +43,13 @@
 #include <arpa/telnet.h>
 #include <arpa/inet.h>
 
+#ifndef IPTOS_LOWCOST
+# define IPTOS_LOWCOST 0x02
+#endif
 #ifndef IPTOS_LOWDELAY
 # define IPTOS_LOWDELAY 0x10
 # define IPTOS_THROUGHPUT 0x08
 # define IPTOS_RELIABILITY 0x04
-# define IPTOS_LOWCOST 0x02
 # define IPTOS_MINCOST IPTOS_LOWCOST
 #endif /* IPTOS_LOWDELAY */
 
@@ -96,8 +98,9 @@
 #include <unistd.h>
 #include <fcntl.h>
 #include <limits.h>
-#include <bsd/stdlib.h>
-#include <bsd/string.h>
+#include <stdlib.h>
+#include <string.h>
+#include <ctype.h>
 #include "atomicio.h"
 
 #ifndef SUN_LEN
@@ -169,6 +172,43 @@
         socklen_t salen, int ctimeout);
 static void quit();
 
+static char* strtonumerrs[] = {
+	"too large",
+	"too small",
+	"invalid"
+};
+
+static long long
+strtonum(
+		const char *nptr,
+		long long minval,
+		long long maxval,
+		const char **errstr)
+{
+	long long val;
+	
+	while (*nptr != '\0' && isspace(*nptr))
+		nptr++;
+	if (*nptr == '\0') {
+		if (errstr != NULL)
+			*errstr = strtonumerrs[2];
+		return 0;
+	}
+	val = atoll(nptr);
+	if (val < minval) {
+		if (errstr != NULL)
+			*errstr = strtonumerrs[1];
+		return 0;
+	}
+	if (val > maxval) {
+		if (errstr != NULL)
+			*errstr = strtonumerrs[0];
+		return 0;
+	}
+	*errstr = NULL;
+	return val;
+}
+
 int
 main(int argc, char *argv[])
 {
--- socks.c
+++ socks.c
@@ -38,7 +38,7 @@
 #include <string.h>
 #include <unistd.h>
 #include <resolv.h>
-#include <bsd/readpassphrase.h>
+#include <readpassphrase.h>
 #include "atomicio.h"
 
 #define SOCKS_PORT	"1080"