PRB: Error: Too Many Files Open

The information in this article applies to:

• Microsoft Visual FoxPro for Windows, versions 3.0 and 3.0b

SYMPTOMS

You may receive the following error if Visual FoxPro reaches its file handle limit of 255:

   Program Error
   Too many files open.

RESOLUTION

To prevent the error from occurring, do not open that many files. If the number of files that are being opened is close to the 255 file limit, open and close files as necessary. To track how many files are open at any given time, create a variable that can store the number of files that already have been opened. For example, if you are opening a database container and one table that has a memo field and an index, 6 files have been opened at this time. They are the DBC, DCT, and DCX files of the database container, and the DBF, CDX, and FPT files of the table. By adding and subtracting the number of files that are opened and closed to the variable each time, you can evaluate when to close any database containers and tables that are not in use so the error will not occur.

NOTE: This error does not occur as quickly in Visual FoxPro 5.0 because it has been designed to open as many files as the operating system allows instead of the 255 file limit currently in Visual FoxPro 3.0.

STATUS

This behavior is by design. Visual FoxPro 3.0 can only open a maximum of 255 files.

MORE INFORMATION

Steps to Reproduce Behavior

Run the following code sample to demonstrate this behavior:

   FOR i = 1 TO 255
    = INKEY(.001)   && Gives create cursor time to keep up
    SELECT (i)
    CREATE CURSOR ("T" + SUBSTR(SYS(2015), 3, 7)) (xyz c(10))
    WAIT WINDOW STR(i) + STR(SELECT()) NOWAIT
   NEXT