Accessing Windows' special named folders in PHP fopen streams - php

http://en.wikipedia.org/wiki/Special_Folders
I am having a problem with accessing a special folder in a fopen stream in php.
Example
$fp = fopen("%USERPROFILE%/Desktop/text.txt", 'wb');
fwrite($fp, $data);
fclose($fp);
I try this with sysinternals process monitor running to try and see what is actually happening and it looks something like this.
C:/xampp/htdocs/test/%USERPROFILE%/Desktop/text.txt PATH NOT FOUND
Well apparently two thing are going wrong, PHP is treating the path as a relative path and the special folder is not being evaluated.

$fp = fopen("{$_ENV['USERPROFILE']}\\Desktop\\text.txt", 'wb');
See $_ENV on the manual and also getenv().
As Johannes Rössel said, this will only work in limited circumstances. You can use this internal function instead:
#include<Shlobj.h>
PHP_FUNCTION(win_get_desktop_folder)
{
char szPath[MAX_PATH];
if (zend_parse_parameters_none() == FAILURE)
RETURN_NULL();
if (SUCCEEDED(SHGetSpecialFolderPathA(NULL, szPath,
CSIDL_DESKTOP, FALSE))) {
RETURN_STRING(szPath, 1);
} else {
RETURN_FALSE;
}
}

Related

fopen doesn´t work with something different than r php

I have a problem with the fopen function and the opening mode argument.
Code
function writeOnFile($url, $text)
{
$fp = fopen($url, "r");
echo "<br>read: ".fgets($fp);
//fwrite($fp, $text);
fclose($fp);
}
If I use "r" as the opening mode the echo line works... but if I change this argument for any other (using the same url file) it stops working and only see "read:" and nothing else.
I tried with "w+" "r+" "a+"... but no one works.
What I am trying to read is a txt file and I changed the permissions of the file and now are 777...
What am I doing wrong?
Given your variable naming, $url suggests you're trying to write to a http://example.com/.... This is not possible. You cannot "write" to a url, because PHP has absolutely NO idea what protocol the remote server is expecting. E.g. PHP by some miracle decides to let this URL through, and uses http POST... but the server is expecting an http PUT. Ooops, that won't work.
As well, never EVER assume an operation on an external resource succeeded. Always assume failure, and treat success as a pleasant surprise:
function writeOnFile($url, $text)
if (!is_writeable($url)) {
die("$url is not writeable");
}
$fp = fopen($url, "w");
if (!$fp) {
die("Unable to open $url for writing");
}
etc...
}

PHP fwrite() not working

I'm writing a function in php, client side I have a canvas image which I use toDataUrl() along with a file name to save the image on the server. The here's the code:
<?php
$imageData=$GLOBALS['HTTP_RAW_POST_DATA'];
$data = json_decode($imageData, true);
$file = $data["file"];
$image = $data["data"];
$filteredData=substr($image, strpos($image, ",")+1);
$unencodedData=base64_decode($filteredData);
$fp = fopen( 'image/' . $file , 'wb' );
fwrite( $fp, $unencodedData);
fclose( $fp );
?>
The thing is that this code works. And for two out of three of the pages I used it on it works fine. The problem is when I copy and pasted it a third time to implement it again, for some reason the file is made on the server except that no data get's written into the file. I don't think it's a problem client side because I write in a debug alert message in the javascript and a debug echo into the PHP and both are able to print out the data fine. I made this short debug file:
<?php
$fp = fopen('data.txt', 'wb');
if(is_writable('data.txt')){
echo "file is writable<br>";
}
if(fwrite($fp, 'test') == FALSE){
echo "failed to write data<br>";
}
fclose($fp);
?>
And the output is
file is writable
failed to write data
I've tried using chmod and setting everything, the folder, the text file before I write to it to 0777 and I still get the same result; the file is made but no data is written into it. Is there anything I'm missing or any other approaches that might help. I haven't found anything on google and am still baffled as to why the same code worked exactly as expected twice before suddenly stopping for no apparent reason.
Thanks in advance.
I know this is an old post, but I had a very similar problem and found a solution (for me at least)! I ran out of disk space on my server, so it could create a 0 byte file, but wouldn't write to it. After I cleared out some space (deleted a 13gb error.log file) everything started working again as expected.
If fopen works but fwrite mysteriously doesn't, check your disk space. 'df -h' is the command to check disk space on a linux server.
instead of $fp = fopen('data.txt', 'wb'); give $fp = fopen('data.txt', 'w'); and try
Changed "wb" to "w"
When you write $fp = fopen('data.txt', 'w'); for your domain website.com having root at /var/www/website/ and if the php file is located at /var/www/website/php/server/file/admin.php or something similar, it will actually create a file at /var/www/website/data.txt
Try giving absolute path or path relative to your domain root to create files like,
$fp = fopen('php/server/file/data.txt', 'w');
Try the find command to see if the file is created anywhere else in the folder directory by using the following in Ubuntu,
find /var/www/website/ -name 'data.txt'
I had this issue, probably can help you solve if you have similar issue.

Php fopen write in css file -> file empty

i have this following php code :
$filename = '/front/style.css';
$cssfile='#h1{font-size:12px}';
if($id_file=fopen($filename, "w+"))
{
echo'file exist';
$id_file=fopen($filename, "w+");
flock($id_file,1);
fwrite($id_file,$cssfile);
flock($id_file,3);
fclose($id_file);
}
else
{
echo "file don t exist";
}
My file is empty but with space.
My file exist and it s writable.
I have nothing in my apache logs.
I m using Mamp with php 5.3.2.
Any ideas ?
Thx
A few mistakes I can see are:
You are using fopen to check if a file exists. That does not work. With the w+ mode PHP will try to create the file if it does not exist. Use the file_exits function to check the existence of a file.
You are opening the same file twice.
Also use PHP constants(LOCK_SH, LOCK_UN) for the second argument of flock. That will make your program more readable.
Updated
Have you checked if its writing to a different directory than you expect? Check your path to see where it defaults to, or even just do a search for the file and see where else it turns up. getcwd() will show what the current working dir is.
Have you checked the return value of fwrite to see if the write is actually working? If fwrite is successful, then try read the file in the code using the same $id_file and see if there is anything there while the program is still running.
You are calling fopen twice. w+ truncates the file and you are writing to the 2nd $id_file so my guess is that its being truncated when the 1st $id_file is being closed.
You can use this approach if your file empty after using fopen w+ option.
// only read
$filename = '/path/to/blah.txt';
$myfile = fopen($filename, "r");
$mydata = fread($myfile, filesize($filename));
$mynewdata = $mydata + 'abc';
fclose($myfile);
// only write
$myfile = fopen($filename, "w");
fwrite($myfile, $mynewdata);
fclose($myfile);

Best way to download a file in PHP

Which would be the best way to download a file from another domain in PHP?
i.e. A zip file.
The easiest one is file_get_contents(), a more advanced way would be with cURL for example. You can store the data to your harddrive with file_put_contents().
normally, the fopen functions work for remote files too, so you could do the following to circumvent the memory limit (but it's slower than file_get_contents)
<?php
$remote = fopen("http://www.example.com/file.zip", "rb");
$local = fopen("local_name_of_file.zip", 'w');
while (!feof($remote)) {
$content = fread($remote, 8192);
fwrite($local, $content);
}
fclose($local);
fclose($remote);
?>
copied from here: http://www.php.net/fread
You may use one code line to do this:
copy(URL, destination);
This function returns TRUE on success and FALSE on failure.

Whats a better way to write this function. Its gets a remote file and copys it localy, in php

So yea, im working on a windows system and while this works locally, know it will break on other peoples servers. Whats a cross platform way to do the same as this
function fetch($get,$put){
file_put_contents($put,file_get_contents($get));
}
I don't see why that would fail unless the other computer is on PHP4. What you would need to do to make that backwards compatible is add functionality to provide replacements for file_get_contents & file_put_contents:
if(version_compare(phpversion(),'5','<')) {
function file_get_contents($file) {
// mimick functionality here
}
function file_put_contents($file,$data) {
// mimick functionality here
}
}
Here would be the solution using simple file operations:
<?php
$file = "http://www.domain.com/thisisthefileiwant.zip";
$hostfile = fopen($file, 'r');
$fh = fopen("thisisthenameofthefileiwantafterdownloading.zip", 'w');
while (!feof($hostfile)) {
$output = fread($hostfile, 8192);
fwrite($fh, $output);
}
fclose($hostfile);
fclose($fh);
?>
Ensure your directory has write permissions enabled. (CHMOD)
Therefore, a replacement for your fetch($get, $put) would be:
function fetch($get, $put) {
$hostfile = fopen($get, 'r');
$fh = fopen($put, 'w');
while (!feof($hostfile)) {
$output = fread($hostfile, 8192);
fwrite($fh, $output);
}
fclose($hostfile);
fclose($fh);
}
Hope it helped! =)
Cheers,
KrX
Shawn's answer is absolute correct, the only thing is that you need to make sure your $put varialable is a valid path on either the Windows Server on the Unix server.
well when i read your question I understood you wanted to bring a file from a remote server to your server locally, this can be done with the FTP extension from php
http://www.php.net/manual/en/function.ftp-fget.php
if this is not what you intent I believe what shawn says is correct
else tell me in the comments and i'll help you more
If the fopen wrappers are not enabled, the curl extension could be: http://php.net/curl

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