51 lines
2.4 KiB
Markdown
51 lines
2.4 KiB
Markdown
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SYNOPSIS
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Cosmopolitan Standard Library.
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OVERVIEW
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This directory defines static archives defining functions, like
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printf(), mmap(), win32, etc. Please note that the Cosmopolitan
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build configuration doesn't link any C/C++ library dependencies
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by default, so you still have the flexibility to choose the one
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provided by your system. If you'd prefer Cosmopolitan, just add
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$(LIBC) and $(CRT) to your linker arguments.
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Your library is compromised of many bite-sized static archives.
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We use the checkdeps tool to guarantee that the contents of the
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archives are organized in a logical way that's easy to use with
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or without our makefile infrastructure, since there's no cyclic
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dependencies.
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The Cosmopolitan Library exports only the most stable canonical
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system calls for all supported operating systems, regardless of
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which platform is used for compilation. We polyfill many of the
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APIs, e.g. read(), write() so they work consistently everywhere
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while other apis, e.g. CreateWindowEx(), might only work on one
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platform, in which case they become no-op functions on others.
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Cosmopolitan polyfill wrappers will usually use the dollar sign
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naming convention, so they may be bypassed when necessary. This
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same convention is used when multiple implementations of string
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library and other performance-critical function are provided to
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allow Cosmopolitan to go fast on both old and newer computers.
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We take an approach to configuration that relies heavily on the
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compiler's dead code elimination pass (libc/dce.h). Most of the
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code is written so that, for example, folks not wanting support
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for OpenBSD can flip a bit in SUPPORT_VECTOR and that code will
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be omitted from the build. The same is true for builds that are
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tuned using -march=native which effectively asks the library to
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not include runtime support hooks for x86 processors older than
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what you use.
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Please note that, unlike Cygwin or MinGW, Cosmopolitan does not
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achieve broad support by bolting on a POSIX emulation layer. We
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do nothing more than (in most cases) stateless API translations
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that get you 90% of the way there in a fast lightweight manner.
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We therefore can't address some of the subtle differences, such
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as the nuances of absolute paths on Windows. Our approach could
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be compared to something more along the lines of, "the Russians
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just used a pencil to write in space", versus spending millions
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researching a pen like NASA.
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