write data to the top in file

[shireeshn]

i have an urgent requirement,

i.e, i have a file which has a data, now i want to write the data to the top of the file. Can we do it ?

ex:-

file content:-
===========
abc
bbc
ccd

i have to write data (sssss) to file after writing it should be

now the file Content
===============
sssss
abc
bbc
ccd


this is a sample file , actull file content will have huge data in file.

 

[TomBascom]

Not really.

This is the same problem as in the editing example. You essentially have to re-write the file.

 

[sdjensen]

Come on Tom, I know you know better. ;p (You will have to rewrite the file but you could have given out some examples)
Of course it can be done. It really depends on how much memory your have or how much time you are ready to spend on the task.​

[LEFT]DEFINE VARIABLE FromName AS CHARACTER NO-UNDO.[/LEFT]
DEFINE VARIABLE ToName AS CHARACTER NO-UNDO.
[LEFT]FromName = "c:\oldfile.txt".[/LEFT]
 
[LEFT]ToName = "c:\newfile.txt".[/LEFT]
 
 
[LEFT]DEFINE VARIABLE bb AS MEMPTR NO-UNDO. 

ASSIGN  
[LEFT]FILE-INFORMATION:FILE-NAME = FromName  
SET-SIZE(bb)               = FILE-INFORMATION:FILE-SIZE. 
INPUT FROM value(FromName) BINARY NO-CONVERT.
IMPORT bb.
INPUT CLOSE.
DEFINE VARIABLE newMem AS MEMPTR    NO-UNDO.
DEFINE VARIABLE newStr AS CHARACTER NO-UNDO.
newStr = "Extra line in top" + chr(13).
OUTPUT TO VALUE(ToName) BINARY NO-CONVERT.
PUT UNFORMATTED newstr SKIP.
OUTPUT CLOSE.
COPY-LOB FROM bb TO FILE toName APPEND.
SET-SIZE(bb) = 0.[/LEFT]
[/LEFT]

Or​

[LEFT]DEFINE VARIABLE FromName AS CHARACTER NO-UNDO.[/LEFT]
DEFINE VARIABLE ToName AS CHARACTER NO-UNDO.
DEFINE VARIABLE InLn AS CHARACTER NO-UNDO.
 
[LEFT]DEFINE STREAM iFile.[/LEFT]
 
[LEFT]DEFINE STREAM oFile.[/LEFT]
 
[LEFT]FromName = "c:\oldfile.txt".[/LEFT]
 
[LEFT]ToName = "c:\newfile.txt".[/LEFT]
 
 
[LEFT]INPUT stream iFile from value(FromName) .[/LEFT]
 
[LEFT]OUTPUT stream oFile to value(ToName) .
PUT STREAM oFile UNFORMATTED "extra line in top" SKIP.[/LEFT]
 
[LEFT]DO WHILE TRUE ON ENDKEY UNDO, LEAVE:[/LEFT]
 
[LEFT]IMPORT STREAM iFile UNFORMATTED Inln.[/LEFT]
 
[LEFT]IF inln = "" THEN

PUT STREAM oFile UNFORMATTED CHR(13).
[LEFT]ELSE 
PUT STREAM oFile UNFORMATTED InLn SKIP.
END.[/LEFT]
[/LEFT]

 
 
 
[LEFT]INPUT STREAM iFile CLOSE.[/LEFT]
 
[LEFT]OUTPUT STREAM oFile CLOSE.[/LEFT]

 

[TomBascom]

Well, yeah, but the ball game was getting started and it is essentially a variation on his question from last week...

 

[shireeshn]

Well, yeah, but the ball game was getting started and it is essentially a variation on his question from last week...

tom, you misunderstood me. sorry it was not my intenstion,I know this way, but i thought can i get any other way to do, that is my intenston and requirement, i have posted this.

i have posted this boz , in this group there are lot of active devlopers , so i have posted, so i can get fast result.

 

[shireeshn]

sorry tom, if have hurt u, i really really have a new requirement.

 

[sdjensen]

Have you tried my examples?

 

[shireeshn]

yes i have tried this, and i got the result as expected.

In first prog i have found copy-LOB,i thing this for open edge. i am not able to work on it boz iam on 9.1D.

Any way thanks.

 

[TomBascom]

I'm not hurt. But I don't have infinite supplies of time either.

BTW, 9.1D is ancient, obsolete and unsupported. It lacks many useful features. Such as COPY-LOB. You should upgrade.

It is, essentially, the same question. You need to rewrite a file. This time instead of replacing some text you are inserting text at the start.

File Handling 101 -- there are only two things that you can easily do "in place":

1) Append to a file.
2) Replace a fixed amount of data with the same amount of data.

Everything else is most easily accomplished by reading the original, and rewriting the output.

/* rewrite.p
 *
 */

define stream inFile.
define stream outFile.

define variable i   as integer no-undo.
define variable txt as character no-undo.

define variable inFileName  as character no-undo format "x(30)".
define variable outFileName as character no-undo format "x(30)".

update inFileName outFileName.

input  stream inFile  from value( inFileName ).
output stream outFile to   value( outFileName ).

/* this is where you would insert text at the top of the file...
 */

repeat:

  txt = ?.

  import stream inFile unformatted txt.
  if txt = ? then leave.

  /* this would be a good place to edit the line, maybe using REPLACE()...
   */

  if txt = "" then
    put stream OutFile unformatted skip(1).
   else
    put stream outFile unformatted txt skip.

end.

input  stream inFile  close.
output stream outFile close.

return.

 

[shireeshn]

Thanks all,

This problem got solved.