Phobos Runtime Library

Phobos is the standard runtime library that comes with the D language compiler. Also, check out the wiki for Phobos.

Philosophy

Each module in Phobos conforms as much as possible to the following design goals. These are goals rather than requirements because D is not a religion, it's a programming language, and it recognizes that sometimes the goals are contradictory and counterproductive in certain situations, and programmers have jobs that need to get done.

Machine and Operating System Independent Interfaces: It's pretty well accepted that gratuitous non-portability should be avoided. This should not be construed, however, as meaning that access to unusual features of an operating system should be prevented.
Simple Operations should be Simple: A common and simple operation, like writing an array of bytes to a file, should be simple to code. I haven't seen a class library yet that simply and efficiently implemented common, basic file I/O operations.
Classes should strive to be independent of one another: It's discouraging to pull in a megabyte of code bloat by just trying to read a file into an array of bytes. Class independence also means that classes that turn out to be mistakes can be deprecated and redesigned without forcing a rewrite of the rest of the class library.
No pointless wrappers around C runtime library functions or OS API functions: D provides direct access to C runtime library functions and operating system API functions. Pointless D wrappers around those functions just adds blather, bloat, baggage and bugs.
Class implementations should use DBC: This will prove that DBC (Contract Programming) is worthwhile. Not only will it aid in debugging the class, but it will help every class user use the class correctly. DBC in the class library will have great leverage.
Use Exceptions for Error Handling: See Error Handling in D.

Imports

Runtime library modules can be imported with the import statement. Each module falls into one of several packages:

std

These are the core modules.

std.windows

Modules specific to the Windows operating system.

std.linux

Modules specific to the Linux operating system.

std.c

Modules that are simply interfaces to C functions. For example, interfaces to standard C library functions will be in std.c, such as std.c.stdio would be the interface to C's stdio.h.

std.c.windows: Modules corresponding to the C Windows API functions.
std.c.linux: Modules corresponding to the C Linux API functions.

etc: This is the root of a hierarchy of modules mirroring the std hierarchy. Modules in etc are not standard D modules. They are here because they are experimental, or for some other reason are not quite suitable for std, although they are still useful.

std: Core library modules

std.base64: Encode/decode base64 format.
std.bind: Bind function arguments.
std.bitarray: Arrays of bits.
std.boxer: Box/unbox types.
std.compiler: Information about the D compiler implementation.
std.conv: Conversion of strings to integers.
std.ctype: Simple character classification
std.date: Date and time functions. Support locales.
std.file: Basic file operations like read, write, append.
std.format: Formatted conversions of values to strings.
std.gc: Control the garbage collector.
std.intrinsic: Compiler built in intrinsic functions
std.math: Include all the usual math functions like sin, cos, atan, etc.
std.md5: Compute MD5 digests.
std.mmfile: Memory mapped files.
object: The root class of the inheritance hierarchy
std.openrj: Basic database.
std.outbuffer: Assemble data into an array of bytes
std.path: Manipulate file names, path names, etc.
std.process: Create/destroy threads.
std.random: Random number generation.
std.recls: Recursively search file system and (currently Windows only) FTP sites.
std.regexp: The usual regular expression functions.
std.socket: Sockets.
std.socketstream: Stream for a blocking, connected Socket.
std.stdint: Integral types for various purposes.
std.stdio: Standard I/O.
std.cstream: Stream I/O.
std.stream: Stream I/O.
std.string: Basic string operations not covered by array ops.
std.system: Inquire about the CPU, operating system.
std.thread: One per thread. Operations to do on a thread.
std.uri: Encode and decode Uniform Resource Identifiers (URIs).
std.utf: Encode and decode utf character encodings.
std.zip: Read/write zip archives.
std.zlib: Compression / Decompression of data.

std.windows: Modules specific to the Windows operating system

std.windows.syserror: Convert Windows error codes to strings.

std.linux: Modules specific to the Linux operating system

std.c: Interface to C functions

std.c.stdio: Interface to C stdio functions like printf().

std.c.windows: Interface to C Windows functions

std.c.windows.windows: Interface to Windows APIs

std.c.linux: Interface to C Linux functions

std.c.linux.linux: Interface to Linux APIs

std.c.stdio

int printf(char* format, ...): C printf() function.