php - How to extract file extension from file with no extension with mime type octet-stream? -

i have large amount of files original file names have been replaced ids database. example, once name word_document.doc 12345. through process have lost original name.

i trying present these files download. person should able download file , view using it's original application. files in 1 of following formats:

• .txt (text)
• .doc (word document)
• .docx (word document)
• .wpd (word perfect)
• .pdf (pdf)
• .rtf (rich text)
• .sxw (star office)
• .odt (open office)

i'm using

$fhandle = finfo_open(fileinfo_mime); $file_mime_type = finfo_file($fhandle, $filepath); 

to mime type , mapping mime type extension.

the problem running of files have mime type of octet-stream. i've read online , type seems miscellaneous type binary files. can't tell extension needs be. in cases works when set .wpd , cases doesn't. same goes .sxw.

symfony2 in 3 steps

1) mime_content_type

$type = mime_content_type($path);  // remove charset (added of php 5.3) if (false !== $pos = strpos($type, ';')) {     $type = substr($type, 0, $pos); }  return $type; 

2) file -b --mime

ob_start(); passthru(sprintf('file -b --mime %s 2>/dev/null', escapeshellarg($path)), $return); if ($return > 0) {     ob_end_clean();      return; }  $type = trim(ob_get_clean()); if (!preg_match('#^([a-z0-9\-]+/[a-z0-9\-\.]+)#i', $type, $match)) {     // it's not type, error message     return; }  return $match[1]; 

3) finfo

if (!$finfo = new \finfo(fileinfo_mime_type, $path)) {     return; }  return $finfo->file($path); 

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after you've got mime-type can extension predefined map, example here or here

$map = array(     'application/msword' => 'doc',     'application/x-msword' => 'doc',     'application/vnd.openxmlformats-officedocument.wordprocessingml.document' => 'docx',     'application/pdf' => 'pdf',     'application/x-pdf' => 'pdf',     'application/rtf' => 'rtf',     'text/rtf' => 'rtf',     'application/vnd.sun.xml.writer' => 'sxw',     'application/vnd.oasis.opendocument.text' => 'odt',     'text/plain' => 'txt', );