🚀 go-pugleaf

In <1cp8uaINNhlq@mizar.usc.edu> sharp@mizar.usc.edu (Malcolm Sharp) writes:

>We have developed an application that when run gives the error message
>"Too many files open."  This error occurs when the 16th file is to
>open by the application.  We have set the "FILES=" statement in
>CONFIG.SYS to 30, 40, 50 and 60 with no luck.

There are (at least) 3 different file limits in most MSDOS applications.

First, the FILES= in CONFIG.SYS limits the total number of open files
across all processes (including TSRs).

Second, unless you specify otherwise by modifying the PSP (DOS 3.0+) or
using INT 21 function 67 (DOS 3.3+), SET HANDLE COUNT, processes can
only have 20 files open.  (See the INTERRUPT LIST under INT 21 function 26
-- CREATE NEW PROGRAM SEGMENT PREFIX for the details of the JFT), you are
limited to 20 handles per process.

Third, many high level languages (Microsoft C, for instance) have a
separate limit of 20 for the number of FILE pointers you can have for
high level I/O operations.  You can still do low level or dos level I/O if
you have handled the first and second limits, or, if you do your own
paging of the FILE (and FILE2) areas, you can essentially do high level
I/O.  (I think this was posted once on comp.os.msdos.programmer

None of this helps you, of course, if you don't have SOME low level access
to the file system.

--
Arthur L. Rubin: a_rubin@dsg4.dse.beckman.com (work) Beckman Instruments/Brea
216-5888@mcimail.com 70707.453@compuserve.com arthur@pnet01.cts.com (personal)
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