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

test/libc/stdio/tmpfile_test.c

@@ -21,12 +21,13 @@
 #include "libc/calls/struct/stat.h"
 #include "libc/calls/syscall_support-sysv.internal.h"
 #include "libc/dce.h"
+#include "libc/limits.h"
 #include "libc/mem/gc.h"
 #include "libc/runtime/runtime.h"
 #include "libc/stdio/stdio.h"
-#include "libc/stdio/temp.h"
 #include "libc/str/str.h"
 #include "libc/sysv/consts/at.h"
+#include "libc/temp.h"
 #include "libc/testlib/testlib.h"
 #include "libc/x/xasprintf.h"
 
@@ -79,7 +80,7 @@ TEST(tmpfile, test) {
 #ifndef __aarch64__
 // TODO(jart): Find way to detect qemu-aarch64
 TEST(tmpfile, renameToRealFile) {
-  if (!IsLinux() || !__is_linux_2_6_23()) return;
+  if (!(IsLinux() && __is_linux_2_6_23())) return;  // need non-ancient linux
   FILE *f;
   f = tmpfile();
   ASSERT_EQ(2, fputs("hi", f));