PENDING= specifier
Standard: F77 F90 F95 F2003
PENDING = variable

The variable must be a scalar logical variable of default kind. This specifier is permitted only in an INQUIRE statement that has an ID= clause.
The PENDING= specifier is assigned the value .TRUE. if the asynchronous operation indicated by the ID= clause is still pending, and .FALSE. if it has completed.

If PENDING= sets the variable to .FALSE., this implicitly “waits” for the operation and the identifier value must not be used again.

ASYNCHRONOUS attribute, ASYNCHRONOUS= specifier, ID= specifier, INQUIRE statement