Difference between revisions of "FOPEN()"

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(Purpose)
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==Purpose==
 
==Purpose==
Function to open an existing ASCII text file
+
Function to open an existing ASCII text file or http URL
 
+
  
 
==Syntax==
 
==Syntax==

Revision as of 15:32, 17 November 2010

Purpose

Function to open an existing ASCII text file or http URL

Syntax

FOPEN(<expC> [,expN>])


See Also

FCREATE(), FCLOSE(), FEOF(), FERROR(), FFLUSH(), FGETS(), FPUTS(), FREAD(), FREADSTR(), FSEEK(), FWRITE(), GETURL(), MEMOREAD(), MEMOWRITE(), TEXTEDIT()


Description

The FOPEN() function opens an existing ASCII text file. It returns a numeric file pointer when the file is opened successfully, or a -1 if unsuccessful. The <expC> is the name of the ASCII file to open. Since the file pointer is required to identify an open file to other file functions, always assign the return value to a memory variable. The optional <expN> determines the file access mode:


<expN> Access Mode
If not specified, read-only
0 Read-only
1 Write only. Existing contents are deleted.
2 Append. Text may be added to the end of the existing contents.


If an error occurs, -1 is returned by the FERROR() function. The FCLOSE() function is used to close a file which has been opened with FOPEN().

From Recital 10, the FOPEN() function can also be used to open http page URLs. Please see below for an example.

Example

use accounts
fp=fopen("existing.file")
if ferror()=-1
    dialog box "The file could not be opened."
else
    string = fgets(fp)
    do while not empty(string)
        ? string
        string = fgets(fp)
    enddo
    ?
endif
fclose(fp)
if ferror()=-1
    dialog box "The file could not be closed."
endif  
 
// http URL example
<!-- twitter.rsp -->
<html>
<body>
<%
fp=fopen("http://twitter.com/recitalsoftware")
do while not feof(fp)
    ? fgets(fp)
enddo
%>
</body>
</html>

Products

Recital, Recital Server