Intermec 6200 Reference Guide

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Since each PEN*KEY 6000 Series Computer has a reset button, there is a

possibility that the user could press it at any time.  In order to maintain data

integrity the application must make sure that all file writes are committed to

disk.  This should be done at the completion of every transaction, e.g. a sales

invoice.  Applications should 

fflush()

 all open streams.  Also, because of DOS

disk buffers and the fact that DOS does not update the directory entry for a file

with each write, applications must do one of the following:

1. Close and reopen all files.
2. Call DOS function 68h for each open file.  All data still in DOS disk buffers

is written to disk immediately, and the file's directory entry is updated.

Example code for Borland C++:

asm mov ah,0x68
asm mov bx,filehandle
asm int 0x21

3. Use DOS function 5D01h, which flushes DOS buffers and updates the

directory entries for all open files.  Example code for Borland C++:

int FileCommit(void)
{
REGS  regs;
SREGS sregs;
// Parameter table used by function 5d01h. Only process_id and
// computer_id are used.
struct {
unsigned int ax;
unsigned int bx;
unsigned int cx;
unsigned int dx;
unsigned int si;
unsigned int di;
unsigned int ds;
unsigned int es;
unsigned int RESERVED;
unsigned int computer_id;
unsigned int process_id;
} dos_parm;

dos_parm.computer_id = 0;

//set current computer

dos_parm.process_id = getpsp();

//set current process

sregs.ds = FP_SEG(&dos_parm);

//set up address of parameter table

regs.x.dx = FP_OFF(&dos_parm);
regs.x.ax = 0x5d01;

//commit all files to disk

intdosx(&regs,&regs,&sregs);
if (regs.x.cflag)

return regs.x.ax;

// if error return code completed ok

return 0;
}

Even if files are committed to disk, a reset can still occur at such a time as to

leave a partial record in a file.  Verify files such as the transaction stream at

program start, and truncate or mark any invalid records as void.
Remove any code used for formatting memory cards for the 4000 Series.  PC

memory cards can be formatted on the PEN*KEY 6000 Series Computer by

loading the CardSoft software and executing FORMAT.COM.