A way to check if data exists? Using PHP

I am pulling a listing of my guilds roster and storing it in our local database, and plan on updating it on a nightly basis to update character information. The issue I have is there are people on the guild roster, that doesn't have a character file to pull because they haven't logged in in years. When I go to retrieve character information, the script stops because it gets to a character who doesn't have information.

So for example, I use to following to get all the members of the guild:

$request = 'http://us.battle.net/api/wow/guild/Elune/SOK?fields=members';

// Make the request
$json = file_get_contents($request);
$json = json_decode($json, true);

I then need to get achievementPoints for each member, which while there is a line items for it in that api call, they are all set to 0, so I then do a call on the character itself to get that information using the following:

function getAchievement($character, $server) {
//Get Roster Data
$request = "http://us.battle.net/api/wow/character/" . $server . "/" . $character;

// Make the request
$json = file_get_contents($request);
$json = json_decode($json, true);
return $json["achievementPoints"];
}

The issue is, as mentioned, some people don't have character information because they haven't logged in a while. For example, Surefoot is listed in the guild roster, but, there is no
http://us.battle.net/api/wow/character/Elune/Surefoot, so I get a bunch of error message similar to this: file_get_contents(http://us.battle.net/api/wow/character/Elune/Surefoot) [function.file-get-contents]: failed to open stream: HTTP request failed! HTTP/1.1 404 Not Found

I am wondering if there is a way to check that it would return something first, similar to php's file_exists as to not get all those error messages. I am using PHP, our server is on version 5.1. Any help or suggestions are welcome. Thanks!