Permanent File Modes

This category of file modes is set at file creation time. The permanent file modes are listed below:

• ctFIXED or ctVLENGTH
• ctPREIMG or ctTRNLOG
• ctLOGIDX
• ctSUPERFILE
• ctDISABLERES
• ctWRITETHRU
• ctCHECKLOCK or ctCHECKREAD

Any of these file modes used when the file is created are attached to the file. Subsequent opens do not need to include these file mode attributes.

The file must be completely recreated to add or remove ctVLENGTH or ctSUPERFILE modes. If you subsequently desire to enable resources, they can be permanently added by EnableCtResource(). UpdateFileMode() can modify the other permanent file modes.

The last three file modes, ctWRITETHRU, ctCHECKLOCK, and ctCHECKREAD, can be added at file open time as temporary modes if they are not already present as permanent modes. This means the feature will be available while the file is opened. Once the file is closed, the feature is not available, unless the file mode is present the next time the file is opened.