#define SQLITE_LOCK_NONE 0 #define SQLITE_LOCK_SHARED 1 #define SQLITE_LOCK_RESERVED 2 #define SQLITE_LOCK_PENDING 3 #define SQLITE_LOCK_EXCLUSIVE 4
SQLite uses one of these integer values as the second argument to calls it makes to the xLock() and xUnlock() methods of an sqlite3_io_methods object.
See also lists of Objects, Constants, and Functions.
SQLite is in the Public Domain.
https://sqlite.org/c3ref/c_lock_exclusive.html