isCOBOL allows you to create a file system interface in COBOL. There is a sample showing how to do this in the $ISCOBOL/sample/trigger folder.

The functions in your file system interface can be made to call isCOBOL's default file system. This allows you to add code before and/or after a file operation at the interface level.

For example, suppose you want to call subprograms named BEFOREWRITE and AFTERWRITE before and after ever WRITE operation. You could edit the sample file system interface ($ISCOBOL/sample/trigger/CobTrigger.cbl) and change the "write" method to the following:

       IDENTIFICATION DIVISION.
       METHOD-ID. MY-WRITE AS "write".
       WORKING-STORAGE SECTION.
       77  RETURN-VALUE OBJECT REFERENCE JLONG.
       LINKAGE SECTION.
       77  THERECORD  OBJECT REFERENCE JBYTEARRAY.
       77  OFFS       OBJECT REFERENCE JINT.  
       77  RECSIZE    OBJECT REFERENCE JINT.     
       77  FLAGLOCK   OBJECT REFERENCE JBOOL.
       PROCEDURE DIVISION USING THERECORD,
                                OFFS,
                                RECSIZE,
                                FLAGLOCK
                      RETURNING RETURN-VALUE.
       MAIN.       

      *Trigger action - start
           CALL "BEFOREWRITE" USING THERECORD, OFFS, 
                RECSIZE, FLAGLOCK.
      *Trigger action - end

           SET RETURN-VALUE TO MY-ISAM:>write (THERECORD,
                                          OFFS,
                                          RECSIZE,
                                          FLAGLOCK).
      *Trigger action - start
           CALL "AFTERWRITE" USING THERECORD, OFFS, 
                RECSIZE, FLAGLOCK.
      *Trigger action - end

           GOBACK.
       END METHOD.  

Please keep in touch and let Veryant Support know how you use or plan on using this feature.

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33. What is the behavior difference of STOP THREAD?
34. What are the defaults for the DATE-ENTRY control DISPLAY-FORMAT property and format styles?
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36. How would I create my own CBL_CHECK_FILE_EXIST routine?
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41. Does isCOBOL run on Linux on System z?
42. Can Veryant recommend a good Web site to find 3rd party JavaBeans?
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50. What algorithm does isCOBOL use to load framework properties (runtime config variables)?
51. How do I configure file locations with environment variables?
52. How can I make my isCOBOL program to be called instead of a C routine when both have the same name?
53. Is your runtime library backward compatible?
54. How do I set iscobol.file.index.FileName with variable file name assignments?
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56. Is there any equivalent to COPY RESOURCE?
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58. Does isCOBOL APS run on z/OS?
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63. What is the best way to profile an isCOBOL program?
64. Why do I get the error message “java.lang.UnsatisfiedLinkError: no ### in java.library.path?
65. Is there a way to have single set of source code that will compile with both ACUCOBOL and isCOBOL?
66. Can you derive isCOBOL object classes from Java and vice versa?
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68. Can the file system (iscobol.file.index) be set programmatically?
69. How can I tell what changes were made in the isCOBOL latest update?
70. Is there any way to use isCOBOL with SCO 5.0.6 (JDK 1.3)?
71. How can I avoid the "java.lang.OutOfMemoryError: PermGen space" error?
72. How do I get more information when I get java.lang.reflect.InvocationTargetException?
73. How can I monitor a jvm started on a remote computer box?
74. Does isCOBOL support Crystal Reports or other Report Writers?
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76. Why do I get the error message "java.lang.ArrayIndexOutOfBoundsException" ?
77. Why do I get the error message "java.lang.NullPointerException" ?
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