50d8d953ce
As of now, the syscall function is implemented as alike to how the linux kernel sycall ABI works, returning -errno upon errors without setting the value of errno. However, this does not conform to the expectations of most software, which expect it to return -1 and set errno, which is how it works on other libcs, which document it accordingly: > The return value is defined by the system call being invoked. In > general, a 0 return value indicates success. A -1 return value > indicates an error, and an error number is stored in errno. - Linux man-pages, syscall(2) > The return value is the return value from the system call, unless > the system call failed. In that case, ‘syscall’ returns ‘-1’ and > sets ‘errno’ to an error code that the system call returned. - glibc manual, (libc)System Calls > When the C-bit is set, syscall returns -1 and sets the external > variable errno (see intro(2)). - 4BSD manual, syscall(2) > A -1 return value indicates an error, and an error code is stored in > errno. - 4.4BSD, FreeBSD, OpenBSD and NetBSD manuals (same quote is found in all of them), syscall(2) This patch corrects the syscall function to work in the same way as in other libcs. |
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| .. | ||
| calls | ||
| crt | ||
| dns | ||
| elf | ||
| fmt | ||
| integral | ||
| intrin | ||
| isystem | ||
| linux | ||
| log | ||
| mem | ||
| nexgen32e | ||
| nt | ||
| runtime | ||
| sock | ||
| stdio | ||
| str | ||
| stubs | ||
| sysv | ||
| testlib | ||
| thread | ||
| time | ||
| tinymath | ||
| vga | ||
| x | ||
| zipos | ||
| ar.h | ||
| assert.h | ||
| atomic.h | ||
| complex.h | ||
| dce.h | ||
| disclaimer.inc | ||
| dos.internal.h | ||
| empty.s | ||
| errno.h | ||
| imag.internal.h | ||
| inttypes.h | ||
| iso646.internal.h | ||
| libc.mk | ||
| limits.h | ||
| literal.h | ||
| mach.internal.h | ||
| macho.internal.h | ||
| macros.internal.h | ||
| math.h | ||
| notice.inc | ||
| notice.internal.h | ||
| paths.h | ||
| README.md | ||
| stdalign.internal.h | ||
| stdckdint.h | ||
| type2str.h | ||
| zip.internal.h | ||
Cosmopolitan Standard Library
This directory defines static archives defining functions, like
printf(), mmap(), win32, etc. Please note that the Cosmopolitan
build configuration doesn't link any C/C++ library dependencies
by default, so you still have the flexibility to choose the one
provided by your system. If you'd prefer Cosmopolitan, just add
$(LIBC) and $(CRT) to your linker arguments.
Your library is compromised of many bite-sized static archives. We use the checkdeps tool to guarantee that the contents of the archives are organized in a logical way that's easy to use with or without our makefile infrastructure, since there's no cyclic dependencies.
The Cosmopolitan Library exports only the most stable canonical
system calls for all supported operating systems, regardless of
which platform is used for compilation. We polyfill many of the
APIs, e.g. read(), write() so they work consistently everywhere
while other apis, e.g. CreateWindowEx(), might only work on one
platform, in which case they become no-op functions on others.
Cosmopolitan polyfill wrappers will usually use the dollar sign naming convention, so they may be bypassed when necessary. This same convention is used when multiple implementations of string library and other performance-critical function are provided to allow Cosmopolitan to go fast on both old and newer computers.
We take an approach to configuration that relies heavily on the
compiler's dead code elimination pass (libc/dce.h). Most of the
code is written so that, for example, folks not wanting support
for OpenBSD can flip a bit in SUPPORT_VECTOR and that code will
be omitted from the build. The same is true for builds that are
tuned using -march=native which effectively asks the library to
not include runtime support hooks for x86 processors older than
what you use.
Please note that, unlike Cygwin or MinGW, Cosmopolitan does not achieve broad support by bolting on a POSIX emulation layer. We do nothing more than (in most cases) stateless API translations that get you 90% of the way there in a fast lightweight manner. We therefore can't address some of the subtle differences, such as the nuances of absolute paths on Windows. Our approach could be compared to something more along the lines of, "the Russians just used a pencil to write in space", versus spending millions researching a pen like NASA.