Reading and writing problems

Question

Assuming you have an access log, each request will create or include values in the log file.

Simulating several requests via ajax, I found that there is always a problem. If you log into the browser console and run the code below, a request will be made within the loop.

setInterval(function()
{
    $('div').each(function()
    {
        $.get( 'url interna' , function( data )
        {
            $('html').text( 'data' )
        });
    })
} , 100 )

Each request by ajax will be recorded a log file, but at a certain point a type error is triggered Permission denied or Invalid argument. I tried to see file_get_contents, file_put_contents, fopen, fwrite and always some error occurs.

---

The file manipulation works properly, I write and read without problems. I looped in 1000 and no errors occur during the recording.

for( $i = 1; $i <= 1000; $i++ )
{
    $fp = fopen( 'file.txt' , 'w' );
    fwrite( $fp , 'texto' );
    fclose( $fp );
}

---

Answer 1

When the file is already opened by one process you cannot edit it in another.

Example: If the arquivo01.php is with the open file (fopen), php. or even another process of arquivo01.php cannot open it while the process that is open with it gives a fclose or be killed by the operating system.

Your loop presents no problems because you open the file closes it and so on...

for( $i = 1; $i <= 1000; $i++ )
{
    $fp = fopen( 'file.txt' , 'w' ); //Abre o arquivo
    fwrite( $fp , 'texto' );
    fclose( $fp ); //Fecha o arquivo
}

To simulate a permission denied error you can use the code below...

$abre_arquivo =  fopen( 'file.txt' , 'w' ); //Ele foi aberto ou seja o espaço de memória esta reservado para uso da variável $abre_arquivo.
for( $i = 1; $i <= 1000; $i++ )
{
    $fp = fopen( 'file.txt' , 'w' ); //Abre o arquivo - Porém ele já esta aberto em outro processo.
    fwrite( $fp , 'texto' );
    fclose( $fp ); //Fecha o arquivo
}