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/syscall-nt.internal.h

@@ -26,7 +26,7 @@ int sys_linkat_nt(int, const char *, int, const char *);
 int sys_madvise_nt(void *, size_t, int);
 int sys_mkdirat_nt(int, const char *, uint32_t);
 int sys_msync_nt(char *, size_t, int);
-int sys_open_nt(int, const char *, uint32_t, int32_t) dontdiscard;
+int sys_open_nt(int, const char *, uint32_t, int32_t) __wur;
 int sys_pipe_nt(int[hasatleast 2], unsigned);
 int sys_renameat_nt(int, const char *, int, const char *);
 int sys_sched_yield_nt(void);