misc library additions/fixes

system/include/libc/sys/_default_fcntl.h

@@ -209,6 +209,11 @@ extern int _open64 _PARAMS ((const char *, int, ...));
 #define POSIX_FADV_DONTNEED 135
 int posix_fadvise(int fd, off_t offset, off_t len, int advice);
 int posix_fallocate(int fd, off_t offset, off_t len);
+#define LOCK_SH 1
+#define LOCK_EX 2
+#define LOCK_UN 4
+#define LOCK_NB 8
+int flock(int fd, int operation);
 
 #ifdef __cplusplus
 }

system/include/libc/sys/dirent.h

@@ -26,6 +26,10 @@ long  telldir(DIR *);
 DIR  *readdir(DIR *);
 int   closedir(DIR *dirp);
 void  rewinddir(DIR *dirp);
+int   scandir(const char *dirp,
+              struct dirent ***namelist,
+              int (*filter)(const struct dirent *),
+              int (*compar)(const struct dirent **, const struct dirent **));
 
 enum {
   DT_UNKNOWN = 0,

system/include/sys/statvfs.h

@@ -20,7 +20,7 @@ struct statvfs {
   int f_namemax;
 };
 
-int statvfs(char *path, struct statvfs *s);
+int statvfs(const char *path, struct statvfs *s);
 
 #ifdef __cplusplus
 }