File_exists problem 1

[freenut]

I am trying to check if a file exists on a remote server, I have the file_exists command working fine on the local server but Im not sure how, what or where to specify the remote servers name if it is possible !!

 

[DRJ478]

Question:

How are you connecting to the remote server?
The answer lies within the fact how you connect.
Different protocols have different ways to detect.

is_file only works on your local file system of your box (unless you have a distributed filesystem such as AFS).

 

[freenut]

Hi DRJ478

Im not too sure of the best way of connecting - I know you can FTP using PHP but find this a little messy. What other ways of connection do you know?? Im only going to check if a file exists so there is no need to copy it or read it.

Thanks
Freenut

 

[skiflyer]

What kind of server are you referring to? A fileserver, a webserver? Or do you really just mean another network client? What pair of OS's are you working with?

-Rob

 

[DRJ478]

I think you can use HTTP as long as the file is web-accessible:

$myUrl = "[URL unfurl="true"]http://www.myServer.com/myPath/myFile.html";[/URL]
# parse the URL so you get the parts you need
$fsPara = parse_url($myUrl);
# open a socket connection to the server
$fID = fsockopen($fsPara["host"], 80);
if (!fID){
   echo("Could not connect");
} else {
   # use a HEAD header to see if it returns status code 200
   fputs($fID, "HEAD $fsPara["path"] HTTP/1.0\r\nHost: $fsPara["host'}\r\n\r\n");
   # read the response
   $head = fread($fID, 4096);
   fclose($fID);
   # check for status 200 in the header
   if (!preg_match('#^HTTP/.*\s+200\sOK\s#i', $head)){
       # ... no file;
   } else {
       # file was accessible through HTTP
   }
}

Caveats:
If the file is not accessible via HTTP it doesn't mean it's not there. Anything else than status 200 fails with the above code.

 

[freenut]

We are using Sco and RH Linux, the files will not be web accessible - what options does that leave us??

Freenut