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Gets line from file pointer
(PHP 4, PHP 5)
Example 628. Reading a file line by line<?phpRelated Examples ( Source code ) » fgets Examples ( Source code ) » fgetss Gets line from file pointer and strip HTML tags Examples ( Source code ) » Close a file after reading Examples ( Source code ) » Using fgets() and feof() Functions Examples ( Source code ) » Opening and Reading a File Line by Line Examples ( Source code ) » Write content to file Examples ( Source code ) » Read in and perform operations on a file line by line Examples ( Source code ) » File based page counter Examples ( Source code ) » Using popen() to Read the Output of the UNIX who Command Examples ( Source code ) » Open socket and read Examples ( Source code ) » Getting and Printing a Web Page with fopen() Examples ( Source code ) » Outputting the Status Lines Returned by Web Servers Examples ( Source code ) » Retrieving a Web Page Using fsockopen() Examples ( Source code ) » Access a Microsoft WebService in PHP Examples ( Source code ) » Feed Validator Examples ( Source code ) » Get WhoIs Information for 270 different tld's Code Examples / Notes » fgetshackajar
When working with VERY large files, php tends to fall over sideways and die. Here is a neat way to pull chunks out of a file very fast and won't stop in mid line, but rater at end of last known line. It pulled a 30+ million line 900meg file through in ~ 24 seconds. NOTE: $buf just hold current chunk of data to work with. If you try "$buf .=" (note 'dot' in from of '=') to append $buff, script will come to grinding crawl around 100megs of data, so work with current data then move on! //File to be opened $file = "huge.file"; //Open file (DON'T USE a+ pointer will be wrong!) $fp = fopen($file, 'r'); //Read 16meg chunks $read = 16777216; //\n Marker $part = 0; while(!feof($fp)) { $rbuf = fread($fp, $read); for($i=$read;$i > 0 || $n == chr(10);$i--) { $n=substr($rbuf, $i, 1); if($n == chr(10))break; //If we are at the end of the file, just grab the rest and stop loop elseif(feof($fp)) { $i = $read; $buf = substr($rbuf, 0, $i+1); break; } } //This is the buffer we want to do stuff with, maybe thow to a function? $buf = substr($rbuf, 0, $i+1); //Point marker back to last \n point $part = ftell($fp)-($read-($i+1)); fseek($fp, $part); } fclose($fp); david
There's an error in the documentation: The file pointer must be valid, and must point to a file successfully opened by fopen() or fsockopen() (and not yet closed by fclose()). You should also add "popen" and "pclose" to the documentation. I'm a new PHP developer and went to verify that I could use "fgets" on commands that I used with "popen". rstefanowski
Take note that fgets() reads 'whole lines'. This means that if a file pointer is in the middle of the line (eg. after fscanf()), fgets() will read the following line, not the remaining part of the currnet line. You could expect it would read until the end of the current line, but it doesn't. It skips to the next full line.
angelo
Sometimes the strings you want to read from a file are not separated by an end of line character. the C style getline() function solves this. Here is my version: <?php function getline( $fp, $delim ) { $result = ""; while( !feof( $fp ) ) { $tmp = fgetc( $fp ); if( $tmp == $delim ) return $result; $result .= $tmp; } return $result; } // Example: $fp = fopen("/path/to/file.ext", 'r'); while( !feof($fp) ) { $str = getline($fp, '|'); // Do something with $str } fclose($fp); ?> dandrews over
Saku's example may also be used like this: <?php @ $pointer = fopen("$DOCUMENT_ROOT/foo.txt", "r"); // the @ suppresses errors so you have to test the pointer for existence if ($pointer) { while (!feof($pointer)) { $preTEXT = fgets($pointer, 999); // $TEXT .= $preTEXT; this is better for a string $ATEXT[$I] = $preTEXT; // maybe better as an array $I++; } fclose($pointer); } ?> lelkesa
Note that - afaik - fgets reads a line until it reaches a line feed (\\n). Carriage returns (\\r) aren't processed as line endings. However, nl2br insterts a <br /> tag before carriage returns as well. This is useful (but not nice - I must admit) when you want to store a more lines in one. <?php function write_lines($text) { $file = fopen('data.txt', 'a'); fwrite($file, str_replace("\n", ' ', $text)."\n"); fclose($file); } function read_all() { $file = fopen('data.txt', 'r'); while (!feof($file)) { $line = fgets($file); echo '<u>Section</u> nl2br'.($line).''; } fclose($file); } ?> Try it. 24-mar-2006 05:36
Macintosh line endings mentioned in docs refer to Mac OS Classic. You don't need this setting for interoperability with unixish OS X.
kpeters at-at monolithss dee oh tee com
It appears that fgets() will return FALSE on EOF (before feof has a chance to read it), so this code will throw an exception: while (!feof($fh)) { $line = fgets($fh); if ($line === false) { throw new Exception("File read error"); } } david_sitller
If you use the example from the command-description, i recommend to trim the $buffer for further use. The line feed ist still at the end of the line. I saw this when using PHP CLI. Like this, checking a file-list for existing entries: $handle = fopen ("/tmp/files.txt", "r"); while (!feof($handle)) { $buffer = fgets($handle, 4096); if (file_exists(rtrim($filename,"\n"))) { echo $buffer; } else { echo $buffer." has been removed." } fclose ($handle); 05-sep-2004 11:05
If you need to simulate an un-buffered fgets so that stdin doesnt hang there waiting for some input (i.e. it reads only if there is data available) use this : <?php function fgets_u($pStdn) { $pArr = array($pStdn); if (false === ($num_changed_streams = stream_select($pArr, $write = NULL, $except = NULL, 0))) { print("\$ 001 Socket Error : UNABLE TO WATCH STDIN.\n"); return FALSE; } elseif ($num_changed_streams > 0) { return trim(fgets($pStdn, 1024)); } } ?> timr
If you need to read an entire file into a string, use file_get_contents(). fgets() is most useful when you need to process the lines of a file separately.
pete
If you have troubles reading binary data with versions <= 4.3.2 then upgrade to 4.3.3 The binary safe implementation seems to have had bugs which were fixed in 4.3.3 anacreo has gmail
I'm using this function to modify the header of a large postscript document on copy... Works extremely quickly so far... function write($filename) { $fh = fopen($this->sourceps,'r'); $fw = fopen($filename,'w'); while (!feof($fh)) { $buffer = fgets($fh); fwrite($fw,$buffer); if (!$setupfound && ereg("^%%BeginSetup",$buffer)) { $setupfound++; if (array_key_exists("$filename",$this->output)) { foreach ($this->output[$filename] as $function => $value) { fwrite($fw,$value); } } stream_copy_to_stream($fh,$fw); } } fclose($fw); fclose($fh); } john
I would like to know if there is a way to pull out information from a ,txt file so that it will show only a section of the file in the browser and no the whole file. these are small files of 10 lines but need to be able to pull specific information in the txt file out into the page. I am new to php and functions and I know how to pull the file into the page but can not seem to get the page to show a character range etc of the information from the file ecvej
I would have expected the same behaviour from these bits of code:- <?php /*This times out correctly*/ while (!feof($fp)) { echo fgets($fp); } /*This times out before eof*/ while ($line=fgets($fp)) { echo $line; } /*A reasonable fix is to set a long timeout*/ stream_set_timeout($fp, 180); while ($line=fgets($fp)) { echo $line; } ?> tavernadelleidee italy
I think that the quickest way of read a (long) file with the rows in reverse order is <?php $myfile = 'myfile.txt'; $command = "tac $myfile > /tmp/myfilereversed.txt"; passthru($command); $ic = 0; $ic_max = 100; // stops after this number of rows $handle = fopen("/tmp/myfilereversed.txt", "r"); while (!feof($handle) && ++$ic<=$ic_max) { $buffer = fgets($handle, 4096); echo $buffer." "; } fclose($handle); ?> It echos the rows while it is reading the file so it is good for long files like logs. Borgonovo peter schlaile
fscanf($file, "%s\n") isn't really a good substitution for fgets(), since it will stop parsing at the first whitespace and not at the end of line! (See the fscanf page for details on this) flame
fread is binary safe, if you are stuck with a pre 4.3 version of PHP.
d
For sockets, If you dont want fgets, fgetc etc... to block if theres no data there. set socket_set_blocking(handle,false); and socket_set_blocking(handle,true); to set it back again.
svayn
fgets is SLOW for scanning through large files. If you don't have PHP 5, use fscanf($file, "%s\n") instead.
saku
As a beginner I would have liked to see "how to read a file into a string for use later and not only how to directly echo the fgets() result. This is what I derived: <?php @ $pointer = fopen("$DOCUMENT_ROOT/foo.txt", "r"); // the @ suppresses errors so you have to test the pointer for existence if ($pointer) { while (!feof($pointer)) { $preTEXT = fgets($pointer, 999); $TEXT = $TEXT . $preTEXT; } fclose($pointer); } ?> sam dot bryan
An easy way to authenticate Windows Domain users from scripts running on a non-Windows or non-Domain box - pass the submitted username and password to an IMAP service on a Windows machine. <?php $server = 'imapserver'; $user = 'user'; $pass = 'pass'; if (authIMAP($user, $pass, $server)) { echo "yay"; } else { echo "nay"; } function authIMAP($user, $pass, $server) { $connection = fsockopen($server, 143, $errno, $errstr, 30); if(!$connection) return false; $output = fgets($connection, 128); // banner fputs($connection, "1 login $user $pass\r\n"); $output = fgets($connection, 128); fputs($connection, "2 logout\r\n"); fclose($connection); if (substr($output, 0, 4) == '1 OK') return true; return false; } ?> |
Change Language
basename chgrp chmod chown clearstatcache copy delete dirname disk_free_space disk_total_space diskfreespace fclose feof fflush fgetc fgetcsv fgets fgetss file_exists file_get_contents file_put_contents file fileatime filectime filegroup fileinode filemtime fileowner fileperms filesize filetype flock fnmatch fopen fpassthru fputcsv fputs fread fscanf fseek fstat ftell ftruncate fwrite glob is_dir is_executable is_file is_link is_readable is_uploaded_file is_writable is_writeable lchgrp lchown link linkinfo lstat mkdir move_uploaded_file parse_ini_file pathinfo pclose popen readfile readlink realpath rename rewind rmdir set_file_buffer stat symlink tempnam tmpfile touch umask unlink |
