@Override
	protected boolean returnErrno(PcodeExecutor<T> executor, int errno) {
		executor.getState()
				.setVar(regEAX,
					executor.getArithmetic().fromConst(-errno, regEAX.getMinimumByteSize()));
		return true;
	}
Construct the system call library for Linux-x86

@param machine the machine emulating the hardware
@param fs the file system to export to the user-space program
@param program a program containing syscall definitions and conventions, likely the target
           program
@param user the "current user" to simulate
Ghidra/Features/SystemEmulation/src/main/java/ghidra/pcode/emu/linux/EmuLinuxX86SyscallUseropLibrary.java