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.

1. How do I compile for compatibility with older versions of Java?
2. When can I get the "java.net.SocketException: Permission denied:connect" message? And how can it be avoided?
3. How do I migrate indexed files to a format that is supported by isCOBOL?
4. How do I resolve "code too large for try statement" errors?
5. How do I prevent hackers from decompiling Java class files to reverse engineer my COBOL application?
6. How can I read an Excel spreadsheet from COBOL?
7. Does SET ADDRESS OF X TO Y work?
8. What Micro Focus library routines are supported?
9. How do I create a desktop shortcut icon to launch my program?
10. Do I need to worry about the compile warning "Note: MYPROG.java uses unchecked or unsafe operations?"
11. How do I resolve a compile error on PIC X(2) USAGE COMP-5?
12. What tools are available for automated functional (regression) testing of a COBOL application?
13. Where can I obtain a copy of the ANSI 2002 COBOL standard?
14. Is there currently a way to debug COBOL and Java source together?
15. How do I increase the maximum Java heap size when compiling?
16. How do I set up isCOBOL to access Vision files?
17. How can I package my application and execute it in a JAR file?
18. How do I turn on debug trace to produce a log file?
19. How do I determine what properties are set?
20. Should I use JISAM or isCOBOL ISAM Server (c-treeACE)?
21. Why do I get a compile error "--S: Invalid open mode" on an OPEN I-O of an ORGANIZATION LINE SEQUENTIAL file?
22. How would I create my own CBL_ALLOC_MEM and CBL_FREE_MEM routines?
23. What is the recommended method for specifying isCOBOL framework properties?
24. What is the best way to control Microsoft Word?
25. How can I use the F10 key in my application without it changing the keyboard focus?
26. Where can I find more information on A$ENCRYPT and A$DECRYPT?
27. How do I get my screens to be the same size and spacing as when I run with ACUCOBOL?
28. How do I use conditional compilation?
29. How do I specify properties or a properties file on the command line?
30. How do I change the icon in the upper left corner of the Window?
31. Does isCOBOL work with Flexus COBOL sp2?
32. How does a program detect at runtime whether it is running standalone GUI, thin client or with Web Direct 2.0?
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?
35. How do I select 11x17 paper size using WIN$PRINTER?
36. Sending SMTP mail
37. How would I create my own CBL_CHECK_FILE_EXIST routine?
38. Is the isCOBOL 2009 SP1 release intended to deploy mainframe applications over the cloud? Or is it an integration mechanism for bringing in cloud data and apps?
39. Where can I learn more about Classpath, the Java class loader, JDK tools and utilities?
40. What are the key technical advantages of isCOBOL?
41. Does isCOBOL run on Linux on System z?
42. Why do I get the error java.lang.NoClassDefFoundError: com/iscobol/rts_n/StopRunException?
43. Can Veryant recommend a good Web site to find 3rd party JavaBeans?
44. Why do I get the error message "Native call not found" and how do I fix the problem?
45. What compile option should I use for ICOBOL compatibility?
46. How do I compile fixed (ANSI) format source that COPYs terminal format source or vice versa?
47. Can I use directory paths in CALL names?
48. Can isCOBOL access a DLL or .so that is in a JAR file?
49. I still get the error : "Missing License: The license key is missing, invalid or has expired!" I can't figure out why
50. What algorithm does isCOBOL use to load framework properties (runtime config variables)?
51. How do I configure file locations with environment variables?
52. How can I make my isCOBOL program to be called instead of a C routine when both have the same name?
53. Is your runtime library backward compatible?
54. How do I set iscobol.file.index.FileName with variable file name assignments?
55. Is there any equivalent to COPY RESOURCE?
56. How do I specify which file status codes I want to use?
57. What is the easiest and/or best way to convert a legacy text-based user interface to a web front end?
58. Does isCOBOL APS run on z/OS?
59. How do I print to a spooler in Unix?
60. How do I write my own replacement for a C$ library routine?
61. Is isCOBOL backward compatible?
62. What should I use for USAGE HANDLE items instead of NULL?
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?
67. How can I tell what changes were made in the isCOBOL latest update?
68. I've heard there is a problem passing pointers to C functions. What is it?
69. Is there any way to use isCOBOL with SCO 5.0.6 (JDK 1.3)?
70. Can the file system (iscobol.file.index) be set programmatically?
71. How do I get more information when I get java.lang.reflect.InvocationTargetException?
72. How can I avoid the "java.lang.OutOfMemoryError: PermGen space" error?
73. How can I monitor a jvm started on a remote computer box?
74. Does isCOBOL support Crystal Reports or other Report Writers?
75. How do I suppress multiple reserved words with the -rw compiler option?
76. Why do I get the error message "java.lang.ArrayIndexOutOfBoundsException" ?
77. Why do I get the error message "java.lang.NullPointerException" ?
78. Can I call an RMCobol program passing parameters to it?
79. How can I avoid, in execution, the "java.lang.OutOfMemoryError: Java heap space" error?
80. What does mean the error NO X11 DISPLAY?
81. How do I resolve the error "java.lang.NoClassDefFoundError" or "java.lang.ClassNotFoundException"?
82. Why do I get the error "Could not load the main class" ?
83. Is there any way to direct the output from the “Print Screen” keyboard key directly to a printer?
84. Did you know that in a string you can replace a text with a new one with a different length by using the C$REPLACE_ALL routine?
85. Did you know how to write custom information inside isCOBOL log file?
86. Did you know you could set properties to configure the PDF'S generation while printing?
87. Did you know you can encrypt the communication with the isCOBOL Server?
88. GIT Server (Linux) - Install and Configuration
89. Activating and Check the isCOBOL License
90. How to search by key with case insensitive on ISAM files
91. How do I point my installed isCOBOL to a different Java location?
92. May I create my own type definitions and reuse them?