oid_modified
oid_modified (oid[, value])
This function returns the current “modified” state for the specified oid. If the specified oid has been modified since the last save operation (or since oid_modified was used to set the oid to “unmodified”), the function returns a one (1). If the oid has not been modified, the function returns a zero (0).
If the optional value parameter is included, the function still returns the current “modified” state of the specified oid, but also sets the “modified” state to the specified value. The value parameter must be either a one (1) for “modified”, or a zero (0) for “unmodified.”
Examples:
$mod = oid_modified(oid_current_tag())
$ret = oid_modified(oid_next(),1)