diff --git a/lib/std/libc/os/posix.c3 b/lib/std/libc/os/posix.c3
index 896399d1d..643320d0a 100644
--- a/lib/std/libc/os/posix.c3
+++ b/lib/std/libc/os/posix.c3
@@ -1,5 +1,7 @@
 module libc @if(env::POSIX);
 
+extern fn isz recv(Fd socket, void *buffer, usz length, CInt flags);
+extern fn isz send(Fd socket, void *buffer, usz length, CInt flags);
 
 extern fn void* dlopen(ZString path, int flags);
 extern fn CInt dlclose(void*);
@@ -188,3 +190,4 @@ struct Termios {
         Speed c_ispeed;
         Speed c_ospeed;
 } 
+
diff --git a/lib/std/libc/os/win32.c3 b/lib/std/libc/os/win32.c3
index 35175056f..c8fd0146d 100644
--- a/lib/std/libc/os/win32.c3
+++ b/lib/std/libc/os/win32.c3
@@ -1,5 +1,5 @@
 module libc @if(env::WIN32);
-
+import std::os::win32;
 
 extern fn CFile __acrt_iob_func(CInt c);
 extern fn CInt _close(Fd fd); def close = _close;
@@ -15,11 +15,13 @@ extern fn Time_t _mkgmtime64(Tm* timeptr); def timegm = _mkgmtime64;
 extern fn Time_t _mktime64(Tm *timeptr); def mktime = _mktime64;
 extern fn usz _msize(void* ptr);
 extern fn CInt _read(Fd fd, void* buffer, CUInt buffer_size);
-extern fn CInt _setjmp(void* frameptr, JmpBuf* buffer) @if(env::WIN32);
+extern fn CInt _setjmp(void* frameptr, JmpBuf* buffer);
 extern fn CFile _wfopen(WString, WString);
 extern fn CFile _wfreopen(WString, WString, CFile);
 extern fn CInt _write(Fd fd, void* buffer, CUInt count);
 extern fn CInt _wremove(WString);
+extern fn int recv(Win32_SOCKET s, void* buf, int len, int flags);
+extern fn int send(Win32_SOCKET s, void* buf, int len, int flags);
 
 struct SystemInfo
 {
diff --git a/lib/std/net/os/posix.c3 b/lib/std/net/os/posix.c3
index 060a00c48..506f270e9 100644
--- a/lib/std/net/os/posix.c3
+++ b/lib/std/net/os/posix.c3
@@ -16,11 +16,11 @@ struct Posix_pollfd
 def Posix_nfds_t = CUInt;
 
 extern fn CInt connect(NativeSocket socket, SockAddrPtr address, Socklen_t address_len);
-extern fn NativeSocket socket(AIFamily af, AISockType type, AIProtocol ip_protocol) @extern("socket");
-extern fn int fcntl(NativeSocket socket, int cmd, ...) @extern("fcntl");
-extern fn CInt bind(NativeSocket socket, SockAddrPtr address, Socklen_t address_len) @extern("bind");
-extern fn CInt listen(NativeSocket socket, CInt backlog) @extern("listen");
-extern fn NativeSocket accept(NativeSocket socket, SockAddrPtr address, Socklen_t* address_len) @extern("accept");
+extern fn NativeSocket socket(AIFamily af, AISockType type, AIProtocol ip_protocol);
+extern fn int fcntl(NativeSocket socket, int cmd, ...);
+extern fn CInt bind(NativeSocket socket, SockAddrPtr address, Socklen_t address_len);
+extern fn CInt listen(NativeSocket socket, CInt backlog);
+extern fn NativeSocket accept(NativeSocket socket, SockAddrPtr address, Socklen_t* address_len);
 extern fn CInt poll(Posix_pollfd* fds, Posix_nfds_t nfds, CInt timeout);
 
 const CUShort POLLIN      = 0x0001;
@@ -55,6 +55,11 @@ fn anyfault socket_error()
 	return convert_error(libc::errno());
 }
 
+macro bool NativeSocket.is_valid(self)
+{
+	return (iptr)self >= 0;
+}
+
 macro void! NativeSocket.close(self)
 {
 	if (libc::close(self))
diff --git a/lib/std/net/os/win32.c3 b/lib/std/net/os/win32.c3
index 2268859a1..9c9079230 100644
--- a/lib/std/net/os/win32.c3
+++ b/lib/std/net/os/win32.c3
@@ -12,7 +12,7 @@ const int FIONREAD = 1074030207;
 const int FIONBIO = -2147195266;
 const int FIOASYNC = -2147195267;
 
-distinct NativeSocket = uptr;
+distinct NativeSocket = inline Win32_SOCKET;
 
 extern fn CInt ioctlsocket(NativeSocket, CLong cmd, CULong *argp);
 extern fn WSAError closesocket(NativeSocket);
@@ -22,6 +22,11 @@ extern fn int bind(NativeSocket, SockAddrPtr address, Socklen_t address_len);
 extern fn int listen(NativeSocket, int backlog);
 extern fn NativeSocket accept(NativeSocket, SockAddrPtr address, Socklen_t* address_len);
 
+macro bool NativeSocket.is_valid(self)
+{
+	return self != (NativeSocket)(uptr)-1;
+}
+
 fn void! NativeSocket.set_non_blocking(self, bool non_blocking)
 {
 	if (ioctlsocket(self, win32::FIONBIO, &&(CULong)non_blocking))
diff --git a/lib/std/net/socket.c3 b/lib/std/net/socket.c3
index bec049ded..a4c109bd0 100644
--- a/lib/std/net/socket.c3
+++ b/lib/std/net/socket.c3
@@ -15,7 +15,7 @@ macro void @loop_over_ai(AddrInfo* ai; @body(NativeSocket fd, AddrInfo* ai))
 	while (ai)
 	{
 		NativeSocket sockfd = os::socket(ai.ai_family, ai.ai_socktype, ai.ai_protocol);
-		if (sockfd > 0)
+		if (sockfd.is_valid())
 		{
 			@body(sockfd, ai);
 		}
@@ -120,8 +120,12 @@ fn bool! Socket.get_option(&self, SocketOption option)
 
 fn usz! Socket.read(&self, char[] bytes) @dynamic
 {
-	isz n = libc::read((Fd)self.sock, bytes.ptr, bytes.len);
-	if (n < 0) return NetError.READ_FAILED?;
+$if env::WIN32:
+	isz n = libc::recv(self.sock, bytes.ptr, (int)bytes.len, 0);
+$else
+	isz n = libc::recv(self.sock, bytes.ptr, bytes.len, 0);
+$endif
+	if (n < 0) return os::socket_error()?;
 	return (usz)n;
 }
 
@@ -129,8 +133,12 @@ fn char! Socket.read_byte(&self) @dynamic => io::@read_byte_using_read(self);
 
 fn usz! Socket.write(&self, char[] bytes) @dynamic
 {
-	isz n = libc::write((Fd)self.sock, bytes.ptr, bytes.len);
-	if (n < 0) return NetError.WRITE_FAILED?;
+$if env::WIN32:
+	isz n = libc::send(self.sock, bytes.ptr, (int)bytes.len, 0);
+$else
+	isz n = libc::send(self.sock, bytes.ptr, bytes.len, 0);
+$endif
+	if (n < 0) return os::socket_error()?;
 	return (usz)n;
 }
 
diff --git a/lib/std/net/tcp.c3 b/lib/std/net/tcp.c3
index 8860643bb..15a2dde85 100644
--- a/lib/std/net/tcp.c3
+++ b/lib/std/net/tcp.c3
@@ -44,7 +44,7 @@ fn TcpSocket! accept(TcpServerSocket* server_socket)
 {
 	TcpSocket socket;
 	socket.sock = os::accept(server_socket.sock, (SockAddrPtr)&socket.ai_addr_storage, &socket.ai_addrlen);
-	if (socket.sock < 0) return NetError.ACCEPT_FAILED?;
+	if (!socket.sock.is_valid()) return NetError.ACCEPT_FAILED?;
 	return socket;
 }
 
diff --git a/releasenotes.md b/releasenotes.md
index 9682586b7..bdd191d46 100644
--- a/releasenotes.md
+++ b/releasenotes.md
@@ -46,10 +46,13 @@
 - Variable in if-try / if-catch cannot be a reused variable name.
 - Vararg interfaces were broken.
 - LLVM codegen for constants in enums could fail.
+- Fixes to the socket functions.
+- Improved output when pointer is out of range.
+- Better error when casting to a distinct fails.
 
 ### Stdlib changes
 
-None
+- `send` and `recv` added to `libc` for Posix / Win32.
 
 ## 0.6.1 Change list
 
diff --git a/src/compiler/bigint.c b/src/compiler/bigint.c
index 86c58d08c..0188caff2 100644
--- a/src/compiler/bigint.c
+++ b/src/compiler/bigint.c
@@ -39,7 +39,7 @@ UNUSED static char digit_to_char(uint8_t digit, bool upper)
 #define LO32(_x) ((_x) & 0xffffffff)
 #define ISNEG(_x) (((uint64_t)_x) >> 63)
 
-char *i128_to_string(Int128 op, uint64_t base, bool is_signed)
+char *i128_to_string(Int128 op, uint64_t base, bool is_signed, bool use_prefix)
 {
 	assert(base >= 2 && base <= 16);
 	static char digits[16] = "0123456789ABCDEF";
@@ -54,9 +54,29 @@ char *i128_to_string(Int128 op, uint64_t base, bool is_signed)
 		*(loc++) = digits[rem.low];
 		op = i128_udiv(op, base_div);
 	} while (!i128_is_zero(op));
-	char *res = malloc_string((size_t)(loc - buffer + 2));
+	char *res = malloc_string((size_t)(loc - buffer + 4));
 	char *c = res;
 	if (add_minus) *(c++) = '-';
+	if (use_prefix)
+	{
+		switch (base)
+		{
+			case 2:
+				*(c++) = '0';
+				*(c++) = 'b';
+				break;
+			case 8:
+				*(c++) = '0';
+				*(c++) = 'o';
+				break;
+			case 16:
+				*(c++) = '0';
+				*(c++) = 'x';
+				break;
+			default:
+				break;
+		}
+	}
 	while (loc > buffer)
 	{
 		*(c++) = *(--loc);
@@ -65,9 +85,10 @@ char *i128_to_string(Int128 op, uint64_t base, bool is_signed)
 	return res;
 }
 
-char *int_to_str(Int i, int radix)
+
+char *int_to_str(Int i, int radix, bool use_prefix)
 {
-	return i128_to_string(i.i, (uint64_t)radix, type_kind_is_signed(i.type));
+	return i128_to_string(i.i, (uint64_t) radix, type_kind_is_signed(i.type), use_prefix);
 }
 
 
diff --git a/src/compiler/compiler_internal.h b/src/compiler/compiler_internal.h
index 09cccb494..5e07a4320 100644
--- a/src/compiler/compiler_internal.h
+++ b/src/compiler/compiler_internal.h
@@ -2097,7 +2097,7 @@ Int int_shr64(Int op, uint64_t);
 Int int_shl64(Int op, uint64_t);
 Real int_to_real(Int op);
 Int int_from_real(Real d, TypeKind type);
-char *int_to_str(Int i, int radix);
+char *int_to_str(Int i, int radix, bool use_prefix);
 bool i128_can_convert_from_double(double x);
 bool i128_can_convert_from_double_signed(double x);
 Int128 i128_from_double(double x);
@@ -2117,7 +2117,7 @@ Int128 i128_not(Int128 op1);
 Int128 i128_mult(Int128 op1, Int128 op2);
 Int128 i128_mult64(Int128 op1, uint64_t op2);
 Int128 i128_from_str(const char *str);
-char *i128_to_string(Int128 op, uint64_t base, bool is_signed);
+char *i128_to_string(Int128 op, uint64_t base, bool is_signed, bool use_prefix);
 bool i128_is_neg(Int128 op);
 CmpRes i128_ucomp(Int128 op1, Int128 op2);
 CmpRes i128_scomp(Int128 op1, Int128 op2);
diff --git a/src/compiler/headers.c b/src/compiler/headers.c
index d1c42d16f..41715436a 100644
--- a/src/compiler/headers.c
+++ b/src/compiler/headers.c
@@ -623,7 +623,7 @@ static void header_gen_global_var(HeaderContext *c, Decl *decl, bool fn_globals,
 		switch (init->const_expr.const_kind)
 		{
 			case CONST_INTEGER:
-				PRINTF("%s\n", int_to_str(init->const_expr.ixx, 10));
+				PRINTF("%s\n", int_to_str(init->const_expr.ixx, 10, false));
 				return;
 			case CONST_FLOAT:
 				PRINTF("%.15g\n", init->const_expr.fxx.f);
diff --git a/src/compiler/number.c b/src/compiler/number.c
index 4b87df189..40b5363be 100644
--- a/src/compiler/number.c
+++ b/src/compiler/number.c
@@ -295,7 +295,7 @@ const char *expr_const_to_error_string(const ExprConst *expr)
 		case CONST_BOOL:
 			return expr->b ? "true" : "false";
 		case CONST_INTEGER:
-			return int_to_str(expr->ixx, 10);
+			return int_to_str(expr->ixx, 10, false);
 		case CONST_FLOAT:
 			return str_printf("%g", expr->fxx.f);
 		case CONST_STRING:
diff --git a/src/compiler/parse_expr.c b/src/compiler/parse_expr.c
index 067ada9db..651ad4ffa 100644
--- a/src/compiler/parse_expr.c
+++ b/src/compiler/parse_expr.c
@@ -1542,12 +1542,12 @@ EXIT:
 		if (type_bits)
 		{
 			PRINT_ERROR_HERE("'%s' does not fit in a '%c%d' literal.",
-			                 i128_to_string(i, radix, true), is_unsigned ? 'u' : 'i', type_bits);
+			                 i128_to_string(i, radix, true, false), is_unsigned ? 'u' : 'i', type_bits);
 		}
 		else
 		{
 			PRINT_ERROR_HERE("'%s' does not fit in an %s literal.",
-			                 i128_to_string(i, radix, true), is_unsigned ? "unsigned int" : "int");
+			                 i128_to_string(i, radix, true, false), is_unsigned ? "unsigned int" : "int");
 		}
 		return poisoned_expr;
 	}
diff --git a/src/compiler/parse_stmt.c b/src/compiler/parse_stmt.c
index ba15e1fa7..162af18a6 100644
--- a/src/compiler/parse_stmt.c
+++ b/src/compiler/parse_stmt.c
@@ -170,7 +170,7 @@ static inline bool parse_asm_scale(ParseContext *c, ExprAsmArg *asm_arg)
 	Int i = value->const_expr.ixx;
 	if (i.i.high)
 	{
-		PRINT_ERROR_HERE("The value is too high for a scale: %s", int_to_str(i, 10));
+		PRINT_ERROR_HERE("The value is too high for a scale: %s", int_to_str(i, 10, false));
 		return false;
 	}
 	switch (i.i.low)
diff --git a/src/compiler/sema_casts.c b/src/compiler/sema_casts.c
index 2d9507ba7..a53491274 100644
--- a/src/compiler/sema_casts.c
+++ b/src/compiler/sema_casts.c
@@ -573,7 +573,8 @@ static bool sema_error_const_int_out_of_range(CastContext *cc, Expr *expr, Expr
 				   expr->const_expr.enum_err_val->var.index,
 				   type_quoted_error_string(to_type));
 	}
-	const char *error_value = expr->const_expr.is_hex ? int_to_str(expr->const_expr.ixx, 16) : expr_const_to_error_string(&expr->const_expr);
+	const char *error_value = expr->const_expr.is_hex ? int_to_str(expr->const_expr.ixx, 16, true)
+	                                                  : expr_const_to_error_string(&expr->const_expr);
 	RETURN_CAST_ERROR(problem, "The value '%s' is out of range for %s, so you need an explicit cast to truncate the value.", error_value,
 			   type_quoted_error_string(to_type));
 }
@@ -727,11 +728,11 @@ static bool rule_int_to_ptr(CastContext *cc, bool is_explicit, bool is_silent)
 		if (!is_explicit) return sema_cast_error(cc, true, is_silent);
 
 		// For if the type doesn't fit, insert an error.
-		if (!int_fits(expr->const_expr.ixx, type_uptr->canonical->type_kind))
+		Int i = expr->const_expr.ixx;
+		if (!int_fits(i, type_uptr->canonical->type_kind))
 		{
 			if (is_silent) return false;
-			RETURN_CAST_ERROR(expr, "'0x%s' does not fit in a pointer.", int_to_str(expr->const_expr.ixx, 16));
-			return false;
+			RETURN_CAST_ERROR(expr, "'%s' does not fit in a pointer.", int_to_str(i, 16, true));
 		}
 		return true;
 	}
@@ -1231,10 +1232,12 @@ static bool rule_to_distinct(CastContext *cc, bool is_explicit, bool is_silent)
 	{
 		cc->to = flat;
 		cc->to_group = flat_group;
-		if (cast_is_allowed(cc, is_explicit, true)) return true;
-		if (is_silent) return false;
-		bool may_explicit = !is_explicit && cast_is_allowed(cc, true, true);
-		return sema_cast_error(cc, may_explicit, is_silent);
+
+		// If it's silent or explicit, just run it:
+		if (is_silent || is_explicit) return cast_is_allowed(cc, is_explicit, is_silent);
+		// Loud and implicit:
+		if (cast_is_allowed(cc, false, true)) return true;
+		return sema_cast_error(cc, cast_is_allowed(cc, true, true), is_silent);
 	}
 
 	cc->to = flat;
diff --git a/src/compiler/sema_decls.c b/src/compiler/sema_decls.c
index 2f123ca9a..672e03b93 100644
--- a/src/compiler/sema_decls.c
+++ b/src/compiler/sema_decls.c
@@ -1518,7 +1518,7 @@ static inline bool sema_analyse_enum(SemaContext *context, Decl *decl, bool *era
 		{
 			SEMA_ERROR(enum_value,
 					   "The enum value would implicitly be %s which does not fit in %s.",
-					   i128_to_string(value, 10, type_is_signed(flat_underlying_type)),
+					   i128_to_string(value, 10, type_is_signed(flat_underlying_type), false),
 					   type_quoted_error_string(type));
 			return false;
 		}
@@ -4011,7 +4011,7 @@ static bool sema_generate_parameterized_name_to_scratch(SemaContext *context, Mo
 				char *maybe_neg = &scratch_buffer.str[scratch_buffer.len];
 				if (type->type_kind == TYPE_I128 || type->type_kind == TYPE_U128)
 				{
-					char *str = int_to_str(param->const_expr.ixx, 10);
+					char *str = int_to_str(param->const_expr.ixx, 10, false);
 					scratch_buffer_append(str);
 				}
 				else
diff --git a/src/compiler/sema_passes.c b/src/compiler/sema_passes.c
index 76ef613d2..2fdfd00e7 100644
--- a/src/compiler/sema_passes.c
+++ b/src/compiler/sema_passes.c
@@ -227,7 +227,7 @@ static Decl **sema_run_exec(CompilationUnit *unit, Decl *decl)
 				scratch_buffer_append_double(arg->const_expr.fxx.f);
 				continue;
 			case CONST_INTEGER:
-				scratch_buffer_append(int_to_str(arg->const_expr.ixx, 10));
+				scratch_buffer_append(int_to_str(arg->const_expr.ixx, 10, false));
 				continue;
 			case CONST_BOOL:
 				scratch_buffer_append(arg->const_expr.b ? "true" : "false");
diff --git a/src/compiler/sema_stmts.c b/src/compiler/sema_stmts.c
index c0c5a9d2a..65f9a96a3 100644
--- a/src/compiler/sema_stmts.c
+++ b/src/compiler/sema_stmts.c
@@ -2198,8 +2198,8 @@ static inline bool sema_check_value_case(SemaContext *context, Type *switch_type
 			sema_error_at(context, extend_span_with_token(expr->span, to_expr->span),
 						  "The range is not valid because the first value (%s) is greater than the second (%s). "
 						  "It would work if you swapped their order.",
-						  int_to_str(const_expr->ixx, 10),
-						  int_to_str(to_const_expr->ixx, 10));
+						  int_to_str(const_expr->ixx, 10, false),
+						  int_to_str(to_const_expr->ixx, 10, false));
 			return false;
 		}
 		Int128 range = int_sub(to_const_expr->ixx, const_expr->ixx).i;
@@ -2774,7 +2774,7 @@ bool sema_analyse_ct_echo_stmt(SemaContext *context, Ast *statement)
 			printf("%f\n", (double)message->const_expr.fxx.f);
 			break;
 		case CONST_INTEGER:
-			puts(int_to_str(message->const_expr.ixx, 10));
+			puts(int_to_str(message->const_expr.ixx, 10, false));
 			break;
 		case CONST_BOOL:
 			puts(message->const_expr.b ? "true" : "false");
diff --git a/src/compiler_tests/tests.c b/src/compiler_tests/tests.c
index f3a661ede..ba553479e 100644
--- a/src/compiler_tests/tests.c
+++ b/src/compiler_tests/tests.c
@@ -153,10 +153,12 @@ void test128()
 	addres = i128_udiv(i128(UINT64_MAX, 0), i128(1, 0));
 	TEST_ASSERT(addres.low == UINT64_MAX && addres.high == 0, "Div failed");
 	addres = i128_sdiv(i128(UINT64_MAX - 1, UINT64_MAX - 1), i128(1, 0));
-	TEST_ASSERTF(addres.low == UINT64_MAX && addres.high == UINT64_MAX, "Div failed %s", i128_to_string(addres, 10, true));
+	TEST_ASSERTF(addres.low == UINT64_MAX && addres.high == UINT64_MAX, "Div failed %s", i128_to_string(addres, 10,
+	                                                                                                    true, false));
 	addres = i128_sdiv(i128(2, 0), i128(UINT64_MAX - 1, UINT64_MAX - 1));
 	printf("-- i128 Div okfefe %x.\n", (unsigned)-2);
-	TEST_ASSERTF(addres.low == UINT64_MAX && addres.high == UINT64_MAX, "Div failed: %s %llx, %llx", i128_to_string(addres, 10, true), (unsigned long long)addres.high, (unsigned long long)addres.low);
+	TEST_ASSERTF(addres.low == UINT64_MAX && addres.high == UINT64_MAX, "Div failed: %s %llx, %llx", i128_to_string(
+			addres, 10, true, false), (unsigned long long)addres.high, (unsigned long long)addres.low);
 	printf("-- i128 Div ok.\n");