Make improvements

- Invent openatemp() API
- Invent O_UNLINK open flag
- Introduce getenv_secure() API
- Remove `git pull` from cosmocc
- Fix utimes() when path is NULL
- Fix mktemp() to never return NULL
- Fix utimensat() UTIME_OMIT on XNU
- Improve utimensat() code for RHEL5
- Turn `argv[0]` C:/ to /C/ on Windows
- Introduce tmpnam() and tmpnam_r() APIs
- Fix more const issues with internal APIs
- Permit utimes() on WIN32 in O_RDONLY mode
- Fix fdopendir() to check fd is a directory
- Fix recent crash regression in landlock make
- Fix futimens(AT_FDCWD, NULL) to return EBADF
- Use workaround so `make -j` doesn't fork bomb
- Rename dontdiscard to __wur (just like glibc)
- Fix st_size for WIN32 symlinks containing UTF-8
- Introduce stdio ext APIs needed by GNU coreutils
- Fix lstat() on WIN32 for symlinks to directories
- Move some constants from normalize.inc to limits.h
- Fix segv with memchr() and memcmp() overlapping page
- Implement POSIX fflush() behavior for reader streams
- Implement AT_SYMLINK_NOFOLLOW for utimensat() on WIN32
- Don't change read-only status of existing files on WIN32
- Correctly handle `0x[^[:xdigit:]]` case in strtol() functions

third_party/xxhash/xxhash.h

@@ -147,7 +147,7 @@
 #include "libc/fmt/fmt.h"
 #include "libc/stdio/dprintf.h"
 #include "libc/stdio/stdio.h"
-#include "libc/stdio/temp.h"
+#include "libc/temp.h"
 #include "third_party/musl/tempnam.h"
  *   #include "libc/assert.h"
  *   #include "third_party/xxhash/xxhash.h"
@@ -1363,7 +1363,7 @@ XXH_PUBLIC_API XXH_PUREF XXH128_hash_t XXH128(XXH_NOESCAPE const void* data, siz
 #include "libc/fmt/fmt.h"
 #include "libc/stdio/dprintf.h"
 #include "libc/stdio/stdio.h"
-#include "libc/stdio/temp.h"
+#include "libc/temp.h"
 #include "third_party/musl/tempnam.h"
  *    #include "libc/calls/calls.h"
 #include "libc/calls/termios.h"
@@ -1375,7 +1375,7 @@ XXH_PUBLIC_API XXH_PUREF XXH128_hash_t XXH128(XXH_NOESCAPE const void* data, siz
 #include "libc/runtime/runtime.h"
 #include "libc/stdio/dprintf.h"
 #include "libc/stdio/rand.h"
-#include "libc/stdio/temp.h"
+#include "libc/temp.h"
 #include "libc/str/str.h"
 #include "libc/sysv/consts/exit.h"
 #include "third_party/getopt/getopt.internal.h"
@@ -1825,7 +1825,7 @@ static void XXH_free(void* p) { (void)p; }
 #include "libc/runtime/runtime.h"
 #include "libc/stdio/dprintf.h"
 #include "libc/stdio/rand.h"
-#include "libc/stdio/temp.h"
+#include "libc/temp.h"
 #include "libc/str/str.h"
 #include "libc/sysv/consts/exit.h"
 #include "third_party/getopt/getopt.internal.h"