how to clear residual garbage in a stack?

Richard Gaskin ambassador at fourthworld.com
Tue May 22 13:18:07 EDT 2018


Neville Smythe wrote:

 > Actually I just did a hex dump of the 8MB file saved from the 1 card
 > stack; and lo! it has an EOF at about the 28KB position, at which
 > point BBEdit stops dumping the file; up to that point it appears to be
 > the correct data for a 1 card stack, no extraneous garbage. But the
 > system reports it as an 8MB file. Doesn’t that mean the file was not
 > closed correctly by the save stack command, or that compact stack is
 > not working correctly to reduce the internal memory and save stack is
 > blindly writing bytes beyond the EOF, so either way it is a bug?

Possibly.  Or it may be an error in the disk driver or a corruption in 
the file system.

EOF is not normally written to a file (at least not since the old CP/M 
days).  My understanding is that modern file systems allow the OS to 
know where the file ends by the length record in the inode; EOF is sent 
only as a flag by the OS during read operations.

I wonder if BBEdit's issue is that it's reading the file as text rather 
than binary, in which case it may be interpreting some binary elements 
as the OS-defined EOF constant.

If you read the stack file as binary in LC what is the length of the data?

-- 
  Richard Gaskin
  Fourth World Systems
  Software Design and Development for the Desktop, Mobile, and the Web
  ____________________________________________________________________
  Ambassador at FourthWorld.com                http://www.FourthWorld.com




More information about the Use-livecode mailing list