How does PHP create temporary files in read-write (w+) mode?

The tmpfile() function in PHP is a built-in function used to create a temporary file with a unique name in read-write (w) mode.

Files created using the tmpfile() function are automatically deleted when closed using fclose() or when there are no remaining references to the file handle.

The temporary file created using the tmpfile() function will also be deleted at the end of the script.

tmpfile()The function does not accept any parameters, it returns a file handle similar to the file handle returned by fopen(), for new files or returns FALSE on failure.

Syntax:

tmpfile()

Return value:

Returns the file handle of the new file on success, and returns FALSE on failure.

Errors And Exception:

1. When the temporary file is closed using fclose(), or when the script ends, the temporary file will be automatically deleted.

2. The function of the tmpfile() function is to return a Boolean value False, but many times it returns a non-Boolean value, and the calculation result of this value is False.

Example 1:

<?php 
$temp_pointer = tmpfile(); 
  
//写入临时文件
fwrite($temp_pointer, &#39;temporary data&#39;); 
  
// 将删除文件
fclose(temp_pointer);

Output:

1

Example 2:

<?php 
$temp_pointer = tmpfile(); 
  
//写入临时文件
fwrite($temp_pointer, "GeeksforGeeks"); 
  
echo fread($temp_pointer, 2048); 
  
fclose($temp_pointer);

Output:

GeeksforGeeks

Related recommendations: "PHP Tutorial"

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