diff --git a/lib/std/core/env.c3 b/lib/std/core/env.c3
index 6a5d7d8b9..32748c8b2 100644
--- a/lib/std/core/env.c3
+++ b/lib/std/core/env.c3
@@ -63,3 +63,27 @@ const usz LLVM_VERSION = $$LLVM_VERSION;
 const bool BENCHMARKING = $$BENCHMARKING;
 const bool TESTING = $$TESTING;
 const usz TEMP_ALLOCATOR_SIZE = 128 * 1024;
+
+macro bool os_is_posix()
+{
+	$switch (OS_TYPE):
+	$case IOS:
+	$case MACOSX:
+	$case NETBSD:
+	$case LINUX:
+	$case KFREEBSD:
+	$case FREEBSD:
+	$case OPENBSD:
+	$case SOLARIS:
+	$case TVOS:
+	$case WATCHOS:
+		return true;
+	$case WIN32:
+	$case WASI:
+	$case EMSCRIPTEN:
+		return false;
+	$default:
+		$echo("Assuming non-Posix environment");
+		return false;
+	$endswitch;
+}
\ No newline at end of file
diff --git a/lib/std/core/os/linux.c3 b/lib/std/core/os/linux.c3
deleted file mode 100644
index 93db894d4..000000000
--- a/lib/std/core/os/linux.c3
+++ /dev/null
@@ -1,17 +0,0 @@
-module std::core::os::linux;
-
-$if (env::OS_TYPE == OsType.LINUX):
-
-extern fn int* __errno_location();
-
-fn int errno() @inline
-{
-    return *__errno_location();
-}
-
-fn void errno_set(int err)
-{
-    *(__errno_location()) = err;
-}
-
-$endif;
diff --git a/lib/std/core/os/macos.c3 b/lib/std/core/os/macos.c3
deleted file mode 100644
index b1f672dc1..000000000
--- a/lib/std/core/os/macos.c3
+++ /dev/null
@@ -1,14 +0,0 @@
-module std::core::os::macos;
-$if (env::OS_TYPE == OsType.MACOSX):
-
-extern fn int* __error();
-
-fn int errno() @inline
-{
-    return *__error();
-}
-fn void errno_set(int err)
-{
-    *(__error()) = err;
-}
-$endif;
diff --git a/lib/std/core/os/windows.c3 b/lib/std/core/os/windows.c3
deleted file mode 100644
index 0a89ba7c4..000000000
--- a/lib/std/core/os/windows.c3
+++ /dev/null
@@ -1,10 +0,0 @@
-module std::core::os::windows;
-
-$if (env::OS_TYPE == OsType.WIN32):
-
-extern fn int getLastError() @stdcall @extname("GetLastError");
-fn int errno() @inline
-{
-    return getLastError();
-}
-$endif;
diff --git a/lib/std/io/io.c3 b/lib/std/io/io.c3
index 4ca624869..3543d0f23 100644
--- a/lib/std/io/io.c3
+++ b/lib/std/io/io.c3
@@ -9,6 +9,30 @@ struct File
     CFile file;
 }
 
+enum Seek
+{
+    SET,
+    CURSOR,
+    END
+}
+
+fault IoError
+{
+    FILE_NOT_FOUND,
+    FILE_NOT_SEEKABLE,
+    FILE_NOT_VALID,
+    FILE_INVALID_POSITION,
+    FILE_OVERFLOW,
+    FILE_IS_PIPE,
+    FILE_EOF,
+    FILE_INCOMPLETE_WRITE,
+    FILE_NOT_DIR,
+    NO_PERMISSION,
+    NAME_TOO_LONG,
+    INTERRUPTED,
+    GENERAL_ERROR,
+    UNKNOWN_ERROR,
+}
 
 fn int putchar(char c) @inline
 {
@@ -39,181 +63,8 @@ fn int println(char *message = "") @inline
     return libc::puts(message);
 }
 
-fn void! File.open(File* file, char[] filename, char[] mode)
-{
-	@pool()
-	{
-	    char* filename_copy = tmalloc(filename.len + 1);
-        char* mode_copy = tmalloc(mode.len + 1);
 
-	    mem::copy(filename_copy, (char*)(filename), filename.len);
-        mem::copy(mode_copy, (char*)(mode), mode.len);
-        filename_copy[filename.len] = 0;
-        mode_copy[filename.len] = 0;
-        file.file = libc::fopen(filename_copy, mode_copy);
-        if (!file.file) return IoError.FILE_NOT_FOUND!;
-	};
-}
 
-enum Seek
-{
-    SET,
-    CURSOR,
-    END
-}
-
-fault IoError
-{
-    FILE_NOT_FOUND,
-    FILE_NOT_SEEKABLE,
-    FILE_NOT_VALID,
-    FILE_INVALID_POSITION,
-    FILE_OVERFLOW,
-    FILE_IS_PIPE,
-    FILE_EOF,
-    FILE_INCOMPLETE_WRITE,
-    INTERRUPTED,
-    UNKNOWN_ERROR,
-}
-
-/**
- * @require file.file != null
- **/
-fn void! File.seek(File *file, long offset, Seek seekMode = Seek.SET)
-{
-    if (libc::fseek(file.file, (SeekIndex)(offset), (int)(seekMode)))
-    {
-        switch (libc::errno())
-        {
-            case errno::EBADF: return IoError.FILE_NOT_SEEKABLE!;
-            case errno::EINVAL: return IoError.FILE_INVALID_POSITION!;
-            case errno::EOVERFLOW: return IoError.FILE_OVERFLOW!;
-            case errno::ESPIPE: return IoError.FILE_IS_PIPE!;
-            default: return IoError.UNKNOWN_ERROR!;
-        }
-    }
-}
-
-/**
- * @require file && file.file != null
- */
-fn void! File.putc(File *file, char c)
-{
-    if (!libc::fputc(c, file.file)) return IoError.FILE_EOF!;
-}
-
-/**
- * @require file != null
- */
-fn void! File.close(File *file) @inline
-{
-    if (file.file && libc::fclose(file.file))
-    {
-        switch (libc::errno())
-        {
-            case errno::ECONNRESET:
-            case errno::EBADF: return IoError.FILE_NOT_VALID!;
-            case errno::EINTR: return IoError.INTERRUPTED!;
-            case errno::EDQUOT:
-            case errno::EFAULT:
-            case errno::EAGAIN:
-            case errno::EFBIG:
-            case errno::ENETDOWN:
-            case errno::ENETUNREACH:
-            case errno::ENOSPC:
-            case errno::EIO: return IoError.FILE_INCOMPLETE_WRITE!;
-            default: return IoError.UNKNOWN_ERROR!;
-        }
-    }
-    file.file = null;
-}
-
-/**
- * @require file && file.file
- */
-fn bool File.eof(File* file) @inline
-{
-    return libc::feof(file.file) != 0;
-}
-
-/**
- * @require file && file.file
- */
-fn usz File.read(File* file, void* buffer, usz items, usz element_size = 1)
-{
-    return libc::fread(buffer, element_size, items, file.file);
-}
-
-/**
- * @param [&in] file
- * @param [&out] buffer
- * @param items
- * @param element_size
- * @require file.file `File must be initialized`
- * @require element_size > 1
- */
-fn usz File.write(File* file, void* buffer, usz items, usz element_size = 1)
-{
-    return libc::fwrite(buffer, element_size, items, file.file);
-}
-
-/**
- * @param [&in] file
- * @require file.file `File must be initialized`
- */
-fn usz! File.println(File* file, char[] string)
-{
-    usz len = string.len;
-    if (len != libc::fwrite(string.ptr, 1, len, file.file)) return IoError.UNKNOWN_ERROR!;
-    if (!libc::putc('\n', file.file)) return IoError.UNKNOWN_ERROR!;
-    return len + 1;
-}
-
-/**
- * @param [&in] file
- * @require file.file `File must be initialized`
- */
-fn String File.getline(File* file, Allocator* allocator = mem::current_allocator())
-{
-	String s = string::new_with_capacity(120, allocator);
-	while (!file.eof())
-	{
-		int c = libc::fgetc(file.file);
-		if (c == -1) break;
-		if (c == '\n') break;
-		s.append_char((char)c);
-	}
-	return s;
-}
-
-/**
- * @param [&in] file
- * @require file.file `File must be initialized`
- * @return "a zero terminated char[] (the pointer may be safely cast into a ZString)"
- */
-fn char[] File.tgetline(File* file)
-{
-
-	String s = file.getline(mem::temp_allocator());
-	ZString z = s.zstr();
-	return z[:s.len()];
-}
-
-fn char! File.getc(File* file)
-{
-	int c = libc::fgetc(file.file);
-	if (c == -1) return IoError.FILE_EOF!;
-	return (char)c;
-}
-
-/**
- * @param [&in] file
- * @require file.file `File must be initialized`
- */
-fn void File.flush(File* file)
-{
-	libc::fflush(file.file);
-}
 
 fn File stdout()
 {
diff --git a/lib/std/io/io_file.c3 b/lib/std/io/io_file.c3
new file mode 100644
index 000000000..0390404e1
--- /dev/null
+++ b/lib/std/io/io_file.c3
@@ -0,0 +1,157 @@
+module std::io;
+import libc;
+
+fn void! File.open(File* file, char[] filename, char[] mode)
+{
+	@pool()
+	{
+	    char* filename_copy = tmalloc(filename.len + 1);
+        char* mode_copy = tmalloc(mode.len + 1);
+
+	    mem::copy(filename_copy, (char*)(filename), filename.len);
+        mem::copy(mode_copy, (char*)(mode), mode.len);
+        filename_copy[filename.len] = 0;
+        mode_copy[filename.len] = 0;
+        file.file = libc::fopen(filename_copy, mode_copy);
+        if (!file.file) return IoError.FILE_NOT_FOUND!;
+	};
+}
+
+/**
+ * @require file.file != null
+ **/
+fn void! File.seek(File *file, long offset, Seek seekMode = Seek.SET)
+{
+    if (libc::fseek(file.file, (SeekIndex)(offset), (int)(seekMode)))
+    {
+        switch (libc::errno())
+        {
+            case errno::EBADF: return IoError.FILE_NOT_SEEKABLE!;
+            case errno::EINVAL: return IoError.FILE_INVALID_POSITION!;
+            case errno::EOVERFLOW: return IoError.FILE_OVERFLOW!;
+            case errno::ESPIPE: return IoError.FILE_IS_PIPE!;
+            default: return IoError.UNKNOWN_ERROR!;
+        }
+    }
+}
+
+/**
+ * @require file && file.file != null
+ */
+fn void! File.putc(File *file, char c)
+{
+    if (!libc::fputc(c, file.file)) return IoError.FILE_EOF!;
+}
+
+/**
+ * @require file != null
+ */
+fn void! File.close(File *file) @inline
+{
+    if (file.file && libc::fclose(file.file))
+    {
+        switch (libc::errno())
+        {
+            case errno::ECONNRESET:
+            case errno::EBADF: return IoError.FILE_NOT_VALID!;
+            case errno::EINTR: return IoError.INTERRUPTED!;
+            case errno::EDQUOT:
+            case errno::EFAULT:
+            case errno::EAGAIN:
+            case errno::EFBIG:
+            case errno::ENETDOWN:
+            case errno::ENETUNREACH:
+            case errno::ENOSPC:
+            case errno::EIO: return IoError.FILE_INCOMPLETE_WRITE!;
+            default: return IoError.UNKNOWN_ERROR!;
+        }
+    }
+    file.file = null;
+}
+
+/**
+ * @require file && file.file
+ */
+fn bool File.eof(File* file) @inline
+{
+    return libc::feof(file.file) != 0;
+}
+
+/**
+ * @require file && file.file
+ */
+fn usz File.read(File* file, void* buffer, usz items, usz element_size = 1)
+{
+    return libc::fread(buffer, element_size, items, file.file);
+}
+
+/**
+ * @param [&in] file
+ * @param [&out] buffer
+ * @param items
+ * @param element_size
+ * @require file.file `File must be initialized`
+ * @require element_size > 1
+ */
+fn usz File.write(File* file, void* buffer, usz items, usz element_size = 1)
+{
+    return libc::fwrite(buffer, element_size, items, file.file);
+}
+
+/**
+ * @param [&in] file
+ * @require file.file `File must be initialized`
+ */
+fn usz! File.println(File* file, char[] string)
+{
+    usz len = string.len;
+    if (len != libc::fwrite(string.ptr, 1, len, file.file)) return IoError.UNKNOWN_ERROR!;
+    if (!libc::putc('\n', file.file)) return IoError.UNKNOWN_ERROR!;
+    return len + 1;
+}
+
+/**
+ * @param [&in] file
+ * @require file.file `File must be initialized`
+ */
+fn String File.getline(File* file, Allocator* allocator = mem::current_allocator())
+{
+	String s = string::new_with_capacity(120, allocator);
+	while (!file.eof())
+	{
+		int c = libc::fgetc(file.file);
+		if (c == -1) break;
+		if (c == '\n') break;
+		s.append_char((char)c);
+	}
+	return s;
+}
+
+/**
+ * @param [&in] file
+ * @require file.file `File must be initialized`
+ * @return "a zero terminated char[] (the pointer may be safely cast into a ZString)"
+ */
+fn char[] File.tgetline(File* file)
+{
+
+	String s = file.getline(mem::temp_allocator());
+	ZString z = s.zstr();
+	return z[:s.len()];
+}
+
+fn char! File.getc(File* file)
+{
+	int c = libc::fgetc(file.file);
+	if (c == -1) return IoError.FILE_EOF!;
+	return (char)c;
+}
+
+/**
+ * @param [&in] file
+ * @require file.file `File must be initialized`
+ */
+fn void File.flush(File* file)
+{
+	libc::fflush(file.file);
+}
diff --git a/lib/std/io/io_fileinfo.c3 b/lib/std/io/io_fileinfo.c3
new file mode 100644
index 000000000..644eeaf7a
--- /dev/null
+++ b/lib/std/io/io_fileinfo.c3
@@ -0,0 +1,81 @@
+module std::io::file;
+import libc;
+
+struct FileInfo
+{
+	ulong size;
+}
+
+$switch (env::OS_TYPE):
+$case MACOSX:
+$case IOS:
+$case WATCHOS:
+$case TVOS:
+private struct DarwinTimespec
+{
+	long tv_sec;
+	long tv_nsec;
+}
+private struct Darwin64Stat
+{
+	int st_dev;
+	ushort st_mode;
+	ushort st_nlink;
+	ulong st_ino;
+	uint st_uid;
+	uint st_gid;
+	int st_rdev;
+	DarwinTimespec st_atimespec; // time of last access
+    DarwinTimespec st_mtimespec; // time of last data modification
+    DarwinTimespec st_ctimespec; // time of last status change
+    DarwinTimespec st_birthtimespec; // time of file creation(birth)
+    long st_size;
+    long st_blocks;
+    int st_blocksize;
+    uint st_flags;
+    uint st_gen;
+    int st_lspare;
+    long[2] st_qspare;
+}
+extern fn int _stat(ZString str, Darwin64Stat* stat) @extname("stat64");
+fn void! FileInfo.read(FileInfo* info, Path path)
+{
+	@pool()
+	{
+		Darwin64Stat stat;
+		int res = _stat(str::tcopy_zstring((char[])path), &stat);
+		if (res != 0)
+		{
+			switch (libc::errno())
+			{
+				case errno::EBADF:
+					return IoError.FILE_NOT_VALID!;
+				case errno::EFAULT:
+					unreachable("Invalid stat");
+				case errno::EIO:
+					return IoError.GENERAL_ERROR!;
+				case errno::EACCES:
+					return IoError.NO_PERMISSION!;
+				case errno::ELOOP:
+					return IoError.NO_PERMISSION!;
+				case errno::ENAMETOOLONG:
+					return IoError.NAME_TOO_LONG!;
+				case errno::ENOENT:
+					return IoError.FILE_NOT_FOUND!;
+				case errno::ENOTDIR:
+					return IoError.FILE_NOT_DIR!;
+				case errno::EOVERFLOW:
+					return IoError.GENERAL_ERROR!;
+				default:
+					return IoError.UNKNOWN_ERROR!;
+			}
+		}
+		info.size = stat.st_size;
+	};
+}
+$default:
+macro void! FileInfo.read(FileInfo* info, Path path)
+{
+	$assert("Unsupported function");
+}
+$endswitch;
\ No newline at end of file
diff --git a/lib/std/libc.c3 b/lib/std/libc/libc.c3
similarity index 74%
rename from lib/std/libc.c3
rename to lib/std/libc/libc.c3
index d6e91a6e9..569808377 100644
--- a/lib/std/libc.c3
+++ b/lib/std/libc/libc.c3
@@ -28,17 +28,13 @@ struct LongDivResult
 
 fn Errno errno()
 {
-    $if (env::OS_TYPE == OsType.WIN32):
-        return (Errno)windows::errno();
-    $elif (env::OS_TYPE == OsType.MACOSX):
-        return (Errno)macos::errno();
-    $elif (env::OS_TYPE == OsType.LINUX):
-        return (Errno)linux::errno();
-    $else:
-        return errno::ENOTRECOVERABLE;
-    $endif;
+	return (Errno)os::errno();
 }
 
+fn void errno_set(Errno e)
+{
+	os::errno_set((int)e);
+}
 
 define TerminateFunction = fn void();
 define CompareFunction = fn int(void*, void*);
@@ -247,46 +243,84 @@ extern fn SignalFunction signal(int sig, SignalFunction function);
 
 module libc::errno;
 
-const Errno EPERM = 1;  /* Operation not permitted */
-const Errno ENOENT = 2;  /* No such file or directory */
-const Errno ESRCH = 3;  /* No such process */
-const Errno EINTR = 4;  /* Interrupted system call */
-const Errno EIO = 5;  /* I/O error */
-const Errno ENXIO = 6;  /* No such device or address */
-const Errno E2BIG = 7;  /* Argument list too long */
-const Errno ENOEXEC = 8;  /* Exec format error */
-const Errno EBADF = 9;  /* Bad file number */
-const Errno ECHILD = 10;  /* No child processes */
-const Errno EAGAIN = 11;  /* Try again */
-const Errno ENOMEM = 12;  /* Out of memory */
-const Errno EACCES = 13;  /* Permission denied */
-const Errno EFAULT = 14;  /* Bad address */
-const Errno ENOTBLK = 15;  /* Block device required */
-const Errno EBUSY = 16;  /* Device or resource busy */
-const Errno EEXIST = 17;  /* File exists */
-const Errno EXDEV = 18;  /* Cross-device link */
-const Errno ENODEV = 19;  /* No such device */
-const Errno ENOTDIR = 20;  /* Not a directory */
-const Errno EISDIR = 21;  /* Is a directory */
-const Errno EINVAL = 22;  /* Invalid argument */
-const Errno ENFILE = 23;  /* File table overflow */
-const Errno EMFILE = 24;  /* Too many open files */
-const Errno ENOTTY = 25;  /* Not a typewriter */
-const Errno ETXTBSY = 26;  /* Text file busy */
-const Errno EFBIG = 27;  /* File too large */
-const Errno ENOSPC = 28;  /* No space left on device */
-const Errno ESPIPE = 29;  /* Illegal seek */
-const Errno EROFS = 30;  /* Read-only file system */
-const Errno EMLINK = 31;  /* Too many links */
-const Errno EPIPE = 32;  /* Broken pipe */
-const Errno EDOM = 33;  /* Math argument out of domain of func */
-const Errno ERANGE = 34;  /* Math result not representable */
-const Errno EDEADLK = 35;  /* Resource deadlock would occur */
-const Errno ENAMETOOLONG = 36;  /* File name too long */
+const Errno EPERM = 1;      // Operation not permitted
+const Errno ENOENT = 2;     // No such file or directory
+const Errno ESRCH = 3;      // No such process
+const Errno EINTR = 4;      // Interrupted system call
+const Errno EIO = 5;        // I/O error
+const Errno ENXIO = 6;      // No such device or address
+const Errno E2BIG = 7;      // Argument list too long
+const Errno ENOEXEC = 8;    // Exec format error
+const Errno EBADF = 9;      // Bad file number
+const Errno ECHILD = 10;    // No child processes
+
+$if (env::OS_TYPE == OsType.MACOSX):
+const Errno EAGAIN = 35;    // Try again Macos
+$else:
+const Errno EAGAIN = 11;    // Try again
+$endif;
+
+const Errno ENOMEM = 12;    // Out of memory
+const Errno EACCES = 13;    // Permission denied
+const Errno EFAULT = 14;    // Bad address
+const Errno ENOTBLK = 15;   // Block device required, not on Win32
+const Errno EBUSY = 16;     // Device or resource busy
+const Errno EEXIST = 17;    // File exists
+const Errno EXDEV = 18;     // Cross-device link
+const Errno ENODEV = 19;    // No such device
+const Errno ENOTDIR = 20;   // Not a directory
+const Errno EISDIR = 21;    // Is a directory
+const Errno EINVAL = 22;    // Invalid argument
+const Errno ENFILE = 23;    // File table overflow
+const Errno EMFILE = 24;    // Too many open files
+const Errno ENOTTY = 25;    // Not a typewriter
+const Errno ETXTBSY = 26;   // Text file busy, not on Win32
+const Errno EFBIG = 27;     // File too large
+const Errno ENOSPC = 28;    // No space left on device
+const Errno ESPIPE = 29;    // Illegal seek
+const Errno EROFS = 30;     // Read-only file system
+const Errno EMLINK = 31;    // Too many links
+const Errno EPIPE = 32;     // Broken pipe
+const Errno EDOM = 33;      // Math argument out of domain of func
+const Errno ERANGE = 34;    // Math result not representable
+
+$if (env::OS_TYPE == OsType.MACOSX):
+const Errno EDEADLK = 11;       // Resource deadlock would occur MacOS
+const Errno ENAMETOOLONG = 63;  // File name too long MacOS
+const Errno ELOOP = 62;         // Too many symbolic links encountered
+const Errno EOVERFLOW = 84;     // Value too large for defined data type Macos
+const Errno ECONNRESET = 54;    // Connection reset by peer Macos
+const Errno ENETDOWN = 50;      // Network is down MacOS
+const Errno ENETUNREACH = 51;   // Network is unreachable MacOS
+const Errno ENETRESET = 52;     // Network dropped connection because of reset MacOS
+
+$elif (env::OS_TYPE == OsType.WIN32):
+const Errno EDEADLK = 36;       // Resource deadlock would occur Win32
+const Errno ENAMETOOLONG = 38;  // File name too long Win32
+const Errno ELOOP = 114;        // Too many symbolic links encountered
+const Errno EOVERFLOW = 132;    // Value too large for defined data type
+const Errno ENETDOWN = 116;     // Network is down
+const Errno ECONNRESET = 108;   // Connection reset by peer
+const Errno ENETUNREACH = 118;  // Network is unreachable
+const Errno ENETRESET = 117;    // Network dropped connection because of reset
+
+$else:
+const Errno EDEADLK = 35;       // Resource deadlock would occur Linux (others?)
+const Errno ENAMETOOLONG = 36;  // File name too long Linux (others?)
+const Errno ELOOP = 40;         // Too many symbolic links encountered
+const Errno EOVERFLOW = 75;     // Value too large for defined data type
+const Errno ENETDOWN = 100;     // Network is down
+const Errno ECONNRESET = 104;   // Connection reset by peer
+const Errno ENETUNREACH = 101;  // Network is unreachable
+const Errno ENETRESET = 102;    // Network dropped connection because of reset
+
+$endif;
+
+
+/*
 const Errno ENOLCK = 37;  /* No record locks available */
 const Errno ENOSYS = 38;  /* Function not implemented */
 const Errno ENOTEMPTY = 39;  /* Directory not empty */
-const Errno ELOOP = 40;  /* Too many symbolic links encountered */
 
 const Errno ENOMSG = 42;  /* No message of desired type */
 const Errno EIDRM = 43;  /* Identifier removed */
@@ -321,7 +355,6 @@ const Errno EPROTO = 71;  /* Protocol error */
 const Errno EMULTIHOP = 72;  /* Multihop attempted */
 const Errno EDOTDOT = 73;  /* RFS specific error */
 const Errno EBADMSG = 74;  /* Not a data message */
-const Errno EOVERFLOW = 75;  /* Value too large for defined data type */
 const Errno ENOTUNIQ = 76;  /* Name not unique on network */
 const Errno EBADFD = 77;  /* File descriptor in bad state */
 const Errno EREMCHG = 78;  /* Remote address changed */
@@ -346,11 +379,7 @@ const Errno EPFNOSUPPORT = 96;  /* Protocol family not supported */
 const Errno EAFNOSUPPORT = 97;  /* Address family not supported by protocol */
 const Errno EADDRINUSE = 98;  /* Address already in use */
 const Errno EADDRNOTAVAIL = 99;  /* Cannot assign requested address */
-const Errno ENETDOWN = 100; /* Network is down */
-const Errno ENETUNREACH = 101; /* Network is unreachable */
-const Errno ENETRESET = 102; /* Network dropped connection because of reset */
 const Errno ECONNABORTED = 103; /* Software caused connection abort */
-const Errno ECONNRESET = 104; /* Connection reset by peer */
 const Errno ENOBUFS = 105; /* No buffer space available */
 const Errno EISCONN = 106; /* Transport endpoint is already connected */
 const Errno ENOTCONN = 107; /* Transport endpoint is not connected */
@@ -360,15 +389,30 @@ const Errno ETIMEDOUT = 110; /* Connection timed out */
 const Errno ECONNREFUSED = 111; /* Connection refused */
 const Errno EHOSTDOWN = 112; /* Host is down */
 const Errno EHOSTUNREACH = 113; /* No route to host */
-const Errno EALREADY = 114; /* Operation already in progress */
-const Errno EINPROGRESS = 115; /* Operation now in progress */
+*/
+$if (env::OS_TYPE == OsType.MACOSX):
+const Errno EINPROGRESS = 36;   // Operation now in progress MacOS
+const Errno EALREADY = 37;      // Operation already in progress MacOS
+const Errno EDQUOT = 69;        // Quota exceeded, MacOS
+
+$elif (env::OS_TYPE == OsType.WIN32):
+const Errno EALREADY = 103;     // Operation already in progress
+const Errno EINPROGRESS = 112;  // Operation now in progress Win32
+const Errno EDQUOT = -122;      // Quota exceeded, not in Win32
+
+$else:
+const Errno EALREADY = 114;     // Operation already in progress
+const Errno EINPROGRESS = 115;  // Operation now in progress
+const Errno EDQUOT = 122;       // Quota exceeded
+$endif;
+
+/*
 const Errno ESTALE = 116; /* Stale NFS file handle */
 const Errno EUCLEAN = 117; /* Structure needs cleaning */
 const Errno ENOTNAM = 118; /* Not a XENIX named type file */
 const Errno ENAVAIL = 119; /* No XENIX semaphores available */
 const Errno EISNAM = 120; /* Is a named type file */
 const Errno EREMOTEIO = 121; /* Remote I/O error */
-const Errno EDQUOT = 122; /* Quota exceeded */
 
 const Errno ENOMEDIUM = 123; /* No medium found */
 const Errno EMEDIUMTYPE = 124; /* Wrong medium type */
@@ -380,5 +424,5 @@ const Errno EKEYREJECTED = 129; /* Key was rejected by service */
 
 const Errno EOWNERDEAD = 130; /* Owner died */
 const Errno ENOTRECOVERABLE = 131; /* State not recoverable */
-
+*/
 
diff --git a/lib/std/libc/os/errno.c3 b/lib/std/libc/os/errno.c3
new file mode 100644
index 000000000..2ffcb675a
--- /dev/null
+++ b/lib/std/libc/os/errno.c3
@@ -0,0 +1,37 @@
+module libc::os;
+
+$switch (env::OS_TYPE):
+
+$case LINUX:
+
+extern fn int* __errno_location();
+
+macro int errno() = *__errno_location();
+macro void errno_set(int err) = *(__errno_location()) = err;
+
+$case MACOSX:
+
+extern fn int* __error();
+macro int errno() = *__error();
+macro void errno_set(int err) = *(__error()) = err;
+
+$case WIN32:
+
+macro int errno()
+{
+	int holder;
+	_get_errno(&holder);
+	return holder;
+}
+
+macro void errno_set(int err) = _set_errno(err);
+
+extern fn void _get_errno(int* result);
+extern fn void _set_errno(int err);
+
+$default:
+
+macro int errno() = 1;
+fn void errno_set(int err) {}
+
+$endswitch;
diff --git a/src/utils/file_utils.c b/src/utils/file_utils.c
index 55a2c91ca..4bb5cc686 100644
--- a/src/utils/file_utils.c
+++ b/src/utils/file_utils.c
@@ -246,7 +246,7 @@ static inline const char *lib_find(const char *exe_path, const char *rel_path)
 	if (err || !S_ISDIR(info.st_mode)) return NULL;
 
 	DEBUG_LOG("Potential lib found, sanity check for libc...");
-	scratch_buffer_append("/libc.c3");
+	scratch_buffer_append("/libc/libc.c3");
 	err = stat(scratch_buffer_to_string(), &info);
 	if (err || !S_ISREG(info.st_mode)) return NULL;
 
diff --git a/src/utils/taskqueue.c b/src/utils/taskqueue.c
index 5d6e39660..2563d0a1c 100644
--- a/src/utils/taskqueue.c
+++ b/src/utils/taskqueue.c
@@ -9,12 +9,12 @@
 typedef struct TaskQueue_
 {
 	pthread_t *threads;
-	int thread_count;
+	volatile int thread_count;
 	pthread_mutex_t lock;
 	pthread_cond_t notify;
-	Task **queue;
-	bool shutdown;
-	int active_threads;
+	volatile Task **queue;
+	volatile bool shutdown;
+	volatile int active_threads;
 } TaskQueue;
 
 static void *taskqueue_thread(void *queue)
@@ -36,7 +36,7 @@ static void *taskqueue_thread(void *queue)
 		}
 		if (task_queue->shutdown) break;
 
-		Task *task = task_queue->queue[vec_size(task_queue->queue) - 1];
+		Task *task = (Task*)task_queue->queue[vec_size(task_queue->queue) - 1];
 		vec_pop(task_queue->queue);
 		task_queue->active_threads++;
 		was_active = true;