diff --git a/vlib/builtin/bare/.checks/linuxsys/linuxsys.v b/vlib/builtin/bare/.checks/linuxsys/linuxsys.v
index 2815313480..bb26c43314 100644
--- a/vlib/builtin/bare/.checks/linuxsys/linuxsys.v
+++ b/vlib/builtin/bare/.checks/linuxsys/linuxsys.v
@@ -7,14 +7,26 @@ const (
 	sample_text_file1 = ""
 )
 
+fn fork_test (test_fn fn(), name string) {
+	//print ("checking")
+	// a := "$name"
+	println (name)
+	child := sys_fork()
+	if child == 0 {
+		test_fn()
+		sys_exit(0)
+	}
+//	pid := sys_wait(0)
+//	assert
+}
+
 fn check_read_write_pipe() {
-	/*
-		Checks the following system calls:
-			sys_pipe
-			sys_write
-			sys_read
-			sys_close
-	*/
+	//	Checks the following system calls:
+	//		sys_pipe
+	//		sys_write
+	//		sys_read
+	//		sys_close
+	//
 	println ("checking pipe read/write")
 	fd[0] = -1
 	fd[1] = -1
@@ -59,12 +71,14 @@ fn check_read_file() {
 			sys_read
 			sys_write
 			sys_close
+			sys_open
 	*/
 	test_file := "sample_text1.txt"
 	sample_text := "Do not change this text.\n"
 	println ("checking read file")
-	fd := sys_open(test_file.str, int(fcntl.o_rdonly), 0)
+	fd, ec := sys_open(test_file.str, .o_rdonly, 0)
 	assert fd > 0
+	assert ec == .enoerror
 	n := sample_text.len
 	c := sys_read(fd, buffer, u64(n*2))
 	assert c == n
@@ -72,12 +86,37 @@ fn check_read_file() {
 		assert sample_text[i] == buffer[i]
 	}
 	assert 0 == sys_close(fd)
+
 	println("read file passed")
 }
 
+fn check_open_file_fail() {
+	println ("checking 'open file fail'")
+	fd1, ec1 := sys_open("./nofilehere".str, .o_rdonly, 0)
+	assert fd1 == -1
+	assert ec1 == .enoent
+	println ("'open file fail' check passed")
+}
+
+/*
+fn check_print() {
+	println ("checking print and println")
+
+	a := sys_pipe(intptr(fd))
+	assert a != -1
+	assert fd[0] != -1
+	assert fd[1] != -1
+
+	//sys_dup2
+	println ("print and println passed")
+}
+*/
+
 fn main() {
 	check_read_write_pipe()
 	check_read_file()
+	// check_print()
+	check_open_file_fail()
 	sys_exit(0)
 }
 
diff --git a/vlib/builtin/bare/.checks/string/string.v b/vlib/builtin/bare/.checks/string/string.v
index 1f469cdc59..b4614097ce 100644
--- a/vlib/builtin/bare/.checks/string/string.v
+++ b/vlib/builtin/bare/.checks/string/string.v
@@ -1,5 +1,7 @@
 module main
 
+__global buffer [128]byte
+
 fn check_string_eq () {
 	println ("checking string_eq")
 	assert "monkey" != "rat"
@@ -8,8 +10,23 @@ fn check_string_eq () {
 	println ("string_eq passed")
 }
 
+fn check_i64_tos() {
+	s0 := i64_tos(buffer, 70, 140, 10)
+	assert s0 == "140"
+
+	s1 := i64_tos(buffer, 70, -160, 10)
+	assert s1 == "-160"
+
+	s2 := i64_tos(buffer, 70, 65537, 16)
+	assert s2 == "10001"
+
+	s3 := i64_tos(buffer, 70, -160000, 10)
+	assert s3 == "-160000"
+}
+
 fn main () {
 	check_string_eq ()
+	check_i64_tos()
 	sys_exit(0)
 }
 
diff --git a/vlib/builtin/bare/builtin_bare.v b/vlib/builtin/bare/builtin_bare.v
index dd83bf654a..0b255a8f99 100644
--- a/vlib/builtin/bare/builtin_bare.v
+++ b/vlib/builtin/bare/builtin_bare.v
@@ -10,7 +10,13 @@ pub fn print(s string) {
 
 pub fn println(s string) {
 	print(s)
-	sys_write(1, "\n".str, 1)
+	print("\n")
+}
+
+pub fn panic(s string) {
+	print('V panic: ')
+	println(s)
+	sys_exit(1)
 }
 
 // replaces panic when -debug arg is passed
@@ -29,16 +35,21 @@ fn panic_debug(line_no int, file,  mod, fn_name, s string) {
 	println('=========================================')
 	sys_exit(1)
 }
+pub fn eprint(s string) {
+	if isnil(s.str) {
+		panic('eprint(NIL)')
+	}
+	sys_write(2, s.str, u64(s.len))
+}
 
-pub fn panic(s string) {
-	print('V panic: ')
-	println(s)
-	sys_exit(1)
+pub fn eprint_ln(s string) {
+	eprint(s)
+	eprint("\n")
 }
 
 pub fn eprintln(s string) {
 	if isnil(s.str) {
 		panic('eprintln(NIL)')
 	}
-	println(s)
+	eprint_ln(s)
 }
diff --git a/vlib/builtin/bare/linuxsys_bare.v b/vlib/builtin/bare/linuxsys_bare.v
index 28ea813469..37a5d4d44c 100644
--- a/vlib/builtin/bare/linuxsys_bare.v
+++ b/vlib/builtin/bare/linuxsys_bare.v
@@ -1,5 +1,24 @@
 module builtin
 
+pub enum wp_sys {
+	wnohang = 0x00000001
+	wuntraced = 0x00000002
+	wstopped = 0x00000002
+	wexited	= 0x00000004
+	wcontinued = 0x00000008
+	wnowait = 0x01000000 // don't reap, just poll status.
+	__wnothread = 0x20000000 // don't wait on children of other threads in this group
+	__wall = 0x40000000 // wait on all children, regardless of type
+	__wclone = 0x80000000 // wait only on non-sigchld children
+}
+
+// First argument to waitid:
+pub enum wi_sys {
+	p_all = 0
+	p_pid = 1
+	p_pgid = 2
+}
+
 pub enum fcntl {
 	fd_cloexec = 0x00000001
 	f_dupfd = 0x00000000
@@ -61,6 +80,7 @@ pub enum fcntl {
 }
 
 pub enum errno {
+	enoerror = 0x00000000
 	e2big = 0x00000007
 	eacces = 0x0000000d
 	eagain = 0x0000000b
@@ -195,9 +215,13 @@ pub fn sys_write(fd int, buf byteptr, count u64) i64 {
 	return i64(sys_call3(1, u64(fd), u64(buf), count))
 }
 
-pub fn sys_open(filename byteptr, flags int, mode int) int {
+pub fn sys_open(filename byteptr, flags fcntl, mode int) (int, errno) {
 	//2 sys_open  const char *filename  int flags int mode
-	return int(sys_call3(2, u64(filename), u64(flags), u64(mode)))
+	rc := int(sys_call3(2, u64(filename), u64(flags), u64(mode)))
+	if rc < 0 {
+		return -1, errno(-rc)
+	}
+	return rc, errno.enoerror
 }
 
 pub fn sys_close(fd int) int {
diff --git a/vlib/builtin/bare/string_bare.v b/vlib/builtin/bare/string_bare.v
index 19a5cdf88c..7d0f700255 100644
--- a/vlib/builtin/bare/string_bare.v
+++ b/vlib/builtin/bare/string_bare.v
@@ -64,6 +64,39 @@ pub fn string_ne (s1, s2 string) bool {
 	return !string_eq(s1,s2)
 }
 
+
+pub fn i64_tos(buf byteptr, len int, n0 i64, base int) string {
+	if base < 2 { panic("base must be >= 2")}
+	if base > 36 { panic("base must be <= 36")}
+
+	mut b := tos(buf, len)
+	mut i := len-1
+
+	mut n := n0
+	neg := n < 0
+	if neg { n = -n }
+
+	b[i--] = 0
+
+	for {
+		c := (n%base) + 48
+		b[i--] = if c > 57 {c+7} else {c}
+		if i < 0 { panic ("buffer to small") }
+		n /= base
+		if n < 1 {break}
+	}
+	if (neg) {
+		if i < 0 { panic ("buffer to small") }
+		b[i--] = 45
+	}
+	offset := i+1
+	b.str = b.str + offset
+	b.len -= (offset+1)
+	return b
+}
+
+
+
 /*
 pub fn (a string) clone() string {
 	mut b := string {
diff --git a/vlib/builtin/string.v b/vlib/builtin/string.v
index 1c0a4e0c1a..38733a1954 100644
--- a/vlib/builtin/string.v
+++ b/vlib/builtin/string.v
@@ -185,31 +185,11 @@ pub fn (s string) replace(rep, with string) string {
 	return tos(b, new_len)
 }
 
-/*
-pub fn (s string) int() int {
-	return strconv.parse_int(s, 0, 32)
-}
-*/
 
 pub fn (s string) int() int {
-	mut neg := false
-	mut i := 0
-	if s[0] == `-` {
-		neg = true
-		i++
-	}
-	else if s[0] == `+` {
-		i++
-	}
-	mut n := 0
-	for C.isdigit(s[i]) {
-		n = 10 * n - int(s[i] - `0`)
-		i++
-	}
-	return if neg { n } else { -n }
+	return int(strconv.parse_int(s,0,32))
 }
 
-
 pub fn (s string) i64() i64 {
 	return strconv.parse_int(s, 0, 64)
 }
@@ -223,23 +203,7 @@ pub fn (s string) f64() f64 {
 }
 
 pub fn (s string) u32() u32 {
-	mut neg := false
-	mut i := 0
-	if s[0] == `-` {
-		neg = true
-		i++
-	}
-	else if s[0] == `+` {
-		i++
-	}
-	mut n := u32(0)
-	for C.isdigit(s[i]) {
-		n = u32(10) * n - u32(s[i] - `0`)
-		i++
-	}
-	return if neg { n } else { -n }
-	//return C.atol(*char(s.str))
-	//return strconv.parse_uint(s, 0, 32)
+	return u32(strconv.parse_uint(s, 0, 32))
 }
 
 pub fn (s string) u64() u64 {
diff --git a/vlib/compiler/tests/enum_hex_test.v b/vlib/compiler/tests/enum_hex_test.v
new file mode 100644
index 0000000000..7b15ccfafd
--- /dev/null
+++ b/vlib/compiler/tests/enum_hex_test.v
@@ -0,0 +1,33 @@
+enum w_hex {
+	a = 0x001
+	b = 0x010
+	c = 0x100
+}
+
+enum w_decimal {
+	a = 1
+	b = 16
+	c = 256
+}
+
+const (
+	ca = 1
+	cb = 16
+	cc = 256
+)
+
+
+fn test_enum_hex() {
+	assert ca == int(w_decimal.a)
+	assert cb == int(w_decimal.b)
+	assert cc == int(w_decimal.c)
+
+	assert int(w_hex.a) == ca
+	assert int(w_hex.b) == cb
+	assert int(w_hex.c) == cc
+
+	assert int(w_hex.a) == int(w_decimal.a)
+	assert int(w_hex.b) == int(w_decimal.b)
+	assert int(w_hex.c) == int(w_decimal.c)
+}
+