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

libc/calls/tmpfd.c

@@ -20,12 +20,14 @@
 #include "libc/calls/calls.h"
 #include "libc/dce.h"
 #include "libc/errno.h"
+#include "libc/limits.h"
 #include "libc/runtime/runtime.h"
-#include "libc/stdio/temp.h"
 #include "libc/str/str.h"
+#include "libc/sysv/consts/at.h"
 #include "libc/sysv/consts/o.h"
+#include "libc/temp.h"
 
-#define _O_TMPFILE 000020200000
+#define O_TMPFILE_LINUX 0x00410000
 
 int _mkstemp(char *, int);
 
@@ -79,7 +81,7 @@ int tmpfd(void) {
   char path[PATH_MAX + 1];
   if (IsLinux()) {
     e = errno;
-    if ((fd = open(kTmpPath, O_RDWR | _O_TMPFILE, 0600)) != -1) {
+    if ((fd = open(kTmpPath, O_RDWR | O_TMPFILE_LINUX, 0600)) != -1) {
       return fd;
     } else {
       errno = e;
@@ -90,7 +92,6 @@ int tmpfd(void) {
   if (!(prog = program_invocation_short_name)) prog = "tmp";
   strlcat(path, prog, sizeof(path));
   strlcat(path, ".XXXXXX", sizeof(path));
-  if ((fd = _mkstemp(path, IsWindows() ? 0x00410000 : 0)) == -1) return -1;
-  if (!IsWindows()) unassert(!unlink(path));
+  if ((fd = openatemp(AT_FDCWD, path, 0, O_UNLINK, 0)) == -1) return -1;
   return fd;
 }