cosmopolitan/libc/linux/read.h

#ifndef COSMOPOLITAN_LIBC_LINUX_READ_H_
#define COSMOPOLITAN_LIBC_LINUX_READ_H_
#if !(__ASSEMBLER__ + __LINKER__ + 0)

forceinline long LinuxRead(long fd, void *data, unsigned long size) {
  long rc;
  asm volatile("syscall"
               : "=a"(rc), "=m"(*(char(*)[size])data)
               : "0"(0), "D"(fd), "S"(data), "d"(size)
               : "rcx", "r11", "memory");
  return rc;
}

#endif /* !(__ASSEMBLER__ + __LINKER__ + 0) */
#endif /* COSMOPOLITAN_LIBC_LINUX_READ_H_ */
Add x86_64-linux-gnu emulator I wanted a tiny scriptable meltdown proof way to run userspace programs and visualize how program execution impacts memory. It helps to explain how things like Actually Portable Executable works. It can show you how the GCC generated code is going about manipulating matrices and more. I didn't feel fully comfortable with Qemu and Bochs because I'm not smart enough to understand them. I wanted something like gVisor but with much stronger levels of assurances. I wanted a single binary that'll run, on all major operating systems with an embedded GPL barrier ZIP filesystem that is tiny enough to transpile to JavaScript and run in browsers too. https://justine.storage.googleapis.com/emulator625.mp4 2020-08-25 11:23:25 +00:00			`#ifndef COSMOPOLITAN_LIBC_LINUX_READ_H_`
			`#define COSMOPOLITAN_LIBC_LINUX_READ_H_`
			`#if !(__ASSEMBLER__ + __LINKER__ + 0)`

Make terminal ui binaries work well everywhere Here's some screenshots of an emulator tui program that was compiled on Linux, then scp'd it to Windows, Mac, and FreeBSD. https://justine.storage.googleapis.com/blinkenlights-cmdexe.png https://justine.storage.googleapis.com/blinkenlights-imac.png https://justine.storage.googleapis.com/blinkenlights-freebsd.png https://justine.storage.googleapis.com/blinkenlights-lisp.png How is this even possible that we have a nontrivial ui binary that just works on Mac, Windows, Linux, and BSD? Surely a first ever achievement. Fixed many bugs. Bootstrapped John McCarthy's metacircular evaluator on bare metal in half the size of Altair BASIC (about 2.5kb) and ran it in emulator for fun and profit. 2020-10-11 04:18:53 +00:00			`forceinline long LinuxRead(long fd, void *data, unsigned long size) {`
Add x86_64-linux-gnu emulator I wanted a tiny scriptable meltdown proof way to run userspace programs and visualize how program execution impacts memory. It helps to explain how things like Actually Portable Executable works. It can show you how the GCC generated code is going about manipulating matrices and more. I didn't feel fully comfortable with Qemu and Bochs because I'm not smart enough to understand them. I wanted something like gVisor but with much stronger levels of assurances. I wanted a single binary that'll run, on all major operating systems with an embedded GPL barrier ZIP filesystem that is tiny enough to transpile to JavaScript and run in browsers too. https://justine.storage.googleapis.com/emulator625.mp4 2020-08-25 11:23:25 +00:00			`long rc;`
			`asm volatile("syscall"`
			`: "=a"(rc), "=m"((char()[size])data)`
			`: "0"(0), "D"(fd), "S"(data), "d"(size)`
			`: "rcx", "r11", "memory");`
			`return rc;`
			`}`

			`#endif /* !(__ASSEMBLER__ + __LINKER__ + 0) */`
			`#endif /* COSMOPOLITAN_LIBC_LINUX_READ_H_ */`