Make more fixes and improvements

- Remove PAGESIZE constant
- Fix realloc() documentation
- Fix ttyname_r() error reporting
- Make forking more reliable on Windows
- Make execvp() a few microseconds faster
- Make system() a few microseconds faster
- Tighten up the socket-related magic numbers
- Loosen restrictions on mmap() offset alignment
- Improve GetProgramExecutableName() with getenv("_")
- Use mkstemp() as basis for mktemp(), tmpfile(), tmpfd()
- Fix flakes in pthread_cancel_test, unix_test, fork_test
- Fix recently introduced futex stack overflow regression
- Let sockets be passed as stdio to subprocesses on Windows
- Improve security of bind() on Windows w/ SO_EXCLUSIVEADDRUSE

tool/emacs/c.lang

@@ -1770,7 +1770,6 @@ Keywords={
 "FLT_MIN",
 "FLT_MAX",
 "__SAUCE__",
-"PAGESIZE",
 "FRAMESIZE",
 "ARG_MAX",
 "PATH_MAX",

tool/emacs/cosmo-cpp-constants.el

@@ -176,7 +176,6 @@
 
 (defconst cosmo-cpp-constants-cosmopolitan
  '("__SAUCE__"
-   "PAGESIZE"
    "APE_STACKSIZE"
    "FRAMESIZE"
    "ARG_MAX"