Saturday, 4 October 2014

fgets in PHP

fgets — Gets line from file pointer
Syntax:

string fgets ( resource $handle [, int $length ] )
Gets a line from file pointer.

Parameters:

handle
The file pointer must be valid, and must point to a file successfully opened by fopen() or fsockopen() (and not yet closed by fclose()).

length
Reading ends when length - 1 bytes have been read, or a newline (which is included in the return value), or an EOF (whichever comes first). If no length is specified, it will keep reading from the stream until it reaches the end of the line.

Note:
Until PHP 4.3.0, omitting it would assume 1024 as the line length. If the majority of the lines in the file are all larger than 8KB, it is more resource efficient for your script to specify the maximum line length.
Return values: Returns a string of up to length - 1 bytes read from the file pointed to by handle. If there is no more data to read in the file pointer, then FALSE is returned.

If an error occurs, FALSE is returned.

Changelog

Version Description
4.3.0 fgets() is now binary safe


Example #1 Reading a file line by line

<?php
$handle = @fopen("/tmp/inputfile.txt", "r");
if ($handle) {
    while (($buffer = fgets($handle, 4096)) !== false) {
        echo $buffer;
    }
    if (!feof($handle)) {
        echo "Error: unexpected fgets() fail\n";
    }
    fclose($handle);
}
?>


Note: If PHP is not properly recognizing the line endings when reading files either on or created by a Macintosh computer, enabling the auto_detect_line_endings run-time configuration option may help resolve the problem.
Note:
People used to the 'C' semantics of fgets() should note the difference in how EOF is returned.

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