wait for copy() to complete

is there a way for me to check to see if a file is copied before continuing to execute a php loop?

i have a for loop, and within th开发者_开发技巧e loop it is going to copy a file. now, i want it so that it waits until the current file is copied before continuing the loop.

example:

for ($i = 1; $i <= 10; $i++)
{
$temp = $_FILES['tmp_name'];
$extension = '.jpg';

copy("$temp_$i_$extension", "$local_$i_$extension");

// not sure what to do here

if (FILE_DONE_COPYING())
{
    CONTINUE_LOOP();
}
else
{
    PAUSE_LOOP();
}
}

thats just an example. i have no clue how to do this...can anyone chime in?

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That's what copy() does in PHP - it blocks until the file is copied. There's nothing you need to do, except checking the return value to see if the operation was successful.

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PHP is taking it line by line, step by step, so it's waiting until copy() is completed

for ($i = 1; $i <= 10; $i++)
{
    $temp = $_FILES['tmp_name'];
    $extension = '.jpg';

    $result = copy("$temp_$i_$extension", "$local_$i_$extension");

    if($result){  
        //done
    }
    else{
        //failed
    }
}

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copy returns true on success and false on failure. Check for that.

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Unless you go through the trouble of using threading and have copy fired asynchronously, PHP will not move to the line after copy until after it has completed.

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copy does wait for completion before continuing execution. It is a syncronous call. But, it can return false if it didn't work, and your copy wont work since $temp_ and $i_ are not defined variables. So maybe you are thinking the copy isn't finishing, when it actually just isn't working at all.

You should use:

copy("{$temp}_{$i}_$extension", "{$local}_{$i}_$extension");

OR

copy($temp.'_'.$i.'_'.$extension, $local.'_'.$i.'_'.$extension);

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What makes you think that copy() will return before it has finished?

You could of course compare filesize of original file and copy to be sure the process is complete.

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You could use a while loop with sleep calls to delay checking, and just exit the while loop once the file exists under the new name.

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I know this is an ancient question but I feel I really need to talk about this problem. COPY is a great command - BUT - it does not work all of the time. I can honestly tell you this. Why? Why does it not always work? Simple - the Operating System is at fault. Here are two examples. One is using a standard disk drive and the second one deals with a Ram disk. The COPY command reads CHUNKS of a file and writes these chunks out to the destination. This means it really does NOT just do a File_get_contents but instead does the fopen(IN), fopen(OUT), while( !EOF(IN) ){ fread(IN), fwrite(OUT) } and then fclose(IN), and fclose(out). It should be noted that these commands try to make sure everything goes ok but if the disk drive buffers what it does - then the file might take a second or two to finish. This can be seen by having a file_exists() on the output file's name. It can come back as FALSE(it IS NOT there). This is because the disk drive's hardware has not caught up with the commands.

I even installed the AMD RamDisk software and ran a program using the above commands (both file_get_contents->file_put_contents and the fopen-fread/fwrite-fclose commands). The same thing happened then also. Every now and then (not always) the file_exists() function returned FALSE because the test got there before the file had finished being created. Don't ask me why - it just would do this.

So what do I suggest? Use the SLEEP() command. Maybe use three(3) seconds (so SLEEP(3);) -after- the COPY() command. I also determined that a CHMOD(, 0777); was a good idea also. With a SLEEP() command after it so it has time to apply the changes. (Which is probably closer to one second).

Now, remember - everyone's hardware is different. So some hardware might work better or faster than the one I am using. So - this is one of those - try it if you are having problems. Or don't - if you are not having problems. It is that simple. So - this is happening to me - I'm using it - it works now that the system gets three seconds to breath - but it might not do anything for you - who has an atomic powered Willy-Wonka mobile which does the impossible before breakfast.

Got it? Good. :-)