埋め込みの説明
@1@ : SIA，STD
例題
[P9504.cob] 000001 @OPTIONS FLAGSW(STDH) 000002 IDENTIFICATION DIVISION. 000003 PROGRAM-ID. P9504. 000004 ENVIRONMENT DIVISION. 000005 DATA DIVISION. 000006 WORKING-STORAGE SECTION. 000007 01 WPTR POINTER. 000008 PROCEDURE DIVISION. 000009 P-START. 000010 SET WPTR TO NULL
P9504.cob 10: JMN9504I-W (STD)表意定数NULLは共通範囲外です．処理を続行します．
