Detecting End-of-File using READLINE command

[Bob Stockler]

On Mon, Sep 13, 2004 at 12:08:29PM -0400, John Hemmer wrote:
| 
| When using the READLINE command to read sequential records
| e.g.
| 
|     bytes=READLINE(handle,destination,length)
| 
| When a line consists of just a newline character, the number of 
| bytes read and returned in "bytes" may be zero. However, there 
| could be many records that follow this line.
| 
| How can I detect the EOF, End-of-File?  Is a negative number 
| of bytes returned?  
| 
| None of the Documentation I have, STN Manual, Online FilePro
| help, etc,  answers these questions.

A GOOD REASON to get Laura's Help Files.  Exerpt:

 v4.5    n = TELL(handle)  - Returns the current position in the file.

 Example:

       then: declare local handle(8,.0)
       then: handle = open("/tmp/myfile.dat","rwt")
         if: handle lt "1"
       then: end
       then: cnt = filesize(handle)
   loop  if:
       then: cnt1 = readline(handle,buffer,"256")
       then: ' do something with "buffer"
         if: TELL(handle) lt cnt
       then: goto loop

   A system independent way to read through an entire file.
   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 See also: CREATE(), OPEN(), READ(), READLINE(), SEEK(), WRITE(), WRITELINE()

Bob (who added the line of ^'s for emphasis)

-- 
Bob Stockler - bob at trebor.iglou.com
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