Number: 840

Date: 26-Apr-84 12':09':39

Submitter: Sannella.PA

Source: Halasz.pa

Subject: COPYBYTES should be able to copy from a file onto itself

Lisp Version: 

Description: '
Date': 24 Apr 84 23':06 PST'
From': Halasz.pa'
Subject': Lisp': COPYBYTES needs to be able to copy from a file onto itself.'
To': LispSupport.pa'
cc': Halasz.pa'
'
Lisp System Date': 16-Apr-84 12':58':26'
Machine': Dorado (Halasz)'
Microcode version': 24,4'
Memory size': 10000'
Frequency': New Feature'
Impact': Fatal'
'
COPYBYTES will not copy a file onto itself, e.g., it will not copy a few bytes from the beginning of a file onto the end of the same file.  Given the absolutely brain-damaged implementation of file pointers in Interlisp, it seems that COPYBYTES ought to make some effort to handle this case gracefully.  Copying parts of file onto other parts of the same file is a very common operation, especially in any applications involving ''databases''.  At the present moment you are forced to use an intermeditae temporary file to copy from a file to itself.  This is not only burdensome, but it sometimes results in a fairly large performance penalty.'
'
Frank'
'


Workaround: 

Test Case: 

Edit-By: 

Edit-Date: 

Attn: Kaplan.pa

Assigned To: 

In/By: 

Disposition: 

System: Operating System

Subsystem: Generic File Operations

Machine: 

Disk: 

Microcode Version: 

Memory Size: 

File Server: 

Server Software Version: 

Difficulty: Moderate

Frequency: Everytime

Impact: Moderate

Priority: Hopefully

Status: Open

Problem Type: Design - Impl

Source Files: