Installation on Windows systems
Table of Contents
Installing PHP on modern Microsoft Windows systems and recommended configuration with common web servers.
If you are looking for information about older systems, such as Windows XP, 2003, 98 or Apache 1.x, see the Legacy Info section.
The Official releases of PHP on Windows are recommended for production use. However, you are welcome to build PHP from Source. You will need a Visual Studio environment. See » Step by Step Build Instructions.
Installing PHP on Azure App Services (aka Microsoft Azure, Windows Azure, or (Windows) Azure Web Apps).
User Contributed Notes 12 notes
If you make changes to your PHP.ini file, consider the following.
(I’m running IIS5 on W2K server. I don’t know about 2K3)
PHP will not «take» the changes until the webserver is restarted, and that doesn’t mean through the MMC. Usually folks just reboot. But you can also use the following commands, for a much faster «turnaround». At a command line prompt, type:
and that will stop the webserver service. Then type:
net start w3svc
and that will start the webserver service again. MUCH faster than a reboot, and you can check your changes faster as a result with the old:
in your page somewhere.
I wish I could remember where I read this tip; it isn’t anything I came up with.
You can have multiple versions of PHP running on the same Apache server. I have seen many different solutions pointing at achieving this, but most of them required installing additional instances of Apache, redirecting ports/hosts, etc., which was not satisfying for me.
Finally, I have come up with the simplest solution I’ve seen so far, limited to reconfiguring Apache’s httpd.conf.
My goal is to have PHP5 as the default scripting language for .php files in my DocumentRoot (which is in my case d:/htdocs), and PHP4 for specified DocumentRoot subdirectories.
Here it is (Apache’s httpd.conf contents):
—————————
# replace with your PHP4 directory
ScriptAlias /php4/ «c:/usr/php4/»
# replace with your PHP5 directory
ScriptAlias /php5/ «c:/usr/php5/»
AddType application/x-httpd-php .php
Action application/x-httpd-php «/php5/php-cgi.exe»
# populate this for every directory with PHP4 code
Action application/x-httpd-php «/php4/php.exe»
# directory where your PHP4 php.ini file is located at
SetEnv PHPRC «c:/usr/php4»
# remember to put this section below the above
# directory where your PHP5 php.ini file is located at
SetEnv PHPRC «c:/usr/php5»
—————————
This solution is not limited to having only two parallel versions of PHP. You can play with httpd.conf contents to have as many PHP versions configured as you want.
You can also use multiple php.ini configuration files for the same PHP version (but for different DocumentRoot subfolders), which might be useful in some cases.
Remember to put your php.ini files in directories specified in lines «SetEnv PHPRC. «, and make sure that there’s no php.ini files in other directories (such as c:\windows in Windows).
And finally, as you can see, I run PHP in CGI mode. This has its advantages and limitations. If you have to run PHP as Apache module, then. sorry — you have to use other solution (the best advice as always is: Google it!).
Hope this helps someone.
If you are installing PHP on Vista just go to David Wang’s blog. http://blogs.msdn.com/david.wang/
archive/2006/06/21/HOWTO-Install-and-Run-PHP-on-IIS7-Part-2.aspx
I made the mistake of setting a ‘wildcard application map’ for PHP on a Windows 2003 / IIS 6.0 / PHP ISAPI installation.
This resulted in «No input file specified» errors whenever I tried to load the default page in my site’s directories. I don’t know why this broke things, but it did.
If anyone has the same problem, this may be the cause.
IIS setup: 403 forbidden error.
We had installed two separate different PHP versions — PHP 5.1.4 followed by 5.2.5.
We configured 5.2.5 php5isapi.dll to be loaded as the .php file type extension.
Despite this, php version 5.1.4 was being loaded. We renamed 5.1.4’s folder and then PHP was not loading at all.
There were no visible references to 5.1.4 in the IIS configuration, but in the file \webConfig.xml, there was a reference to 5.1.4’s isapi under IISFilters.
To fix this problem, we added version 5.2.5’s php5isapi.dll to the ISAPI Filter category for the web site, in the IIS control panel.
I installed by Microsoft Installer, manually, whatever I always received de same error from IIS7.
HTTP Error 404.3 — Not Found
The page you are requesting cannot be served because of the extension configuration. If the page is a script, add a handler. If the file should be downloaded, add a MIME map.
The IIS7 interface is quite diferent and are not all together like IIS6
The 5.3 version have not any of those files: php5stdll, php5isapi.dll. etc.
The installer puts others files in handlers and I decided to use them as substitutes. Nothing done!
After that, I discovered that installer do not install these files within the sites, but in the root default site configuration of IIS7.
So, I copied the root configuration to my site and them it worked (all others procedures were done e.g. copy php.ini to windows folder)
If you get 404 page not found on Windows/IIS5, have a look at C:\SYSTEM32\INETSRV\URLSCAN
There is a .ini file there that prevents some files from being served by IIS, even if they exist, instead IIS will give a 404. The urlscan logfile (same place) should give you some insight into what parameter is preventing a page from loading, if any.
Here’s how to run dual PHP instances with PHP 5.2 and any previous PHP on Windows 2003:
1. Right-click My Computer, go to Advanced tab, and click on Environment Variables.
Add the two installations and their EXT directories to the Path variable. For example, add:
c:\php;c:\php\ext;c:\TMAS\php;c:\tmas\php\ext;
Then, add the newer PHP version’s directory as a variable called PHPRC. For example:
Variable:PHPRC
Value: C:\PHP
Click OK to close the Environment Variables window, and click OK to close System Properties.
2. In registry, under HKEY_LOCAL_MACHINE>SOFTWARE>PHP, add a REG_SZ key called iniFilePath and give it a value
of the directory where the older PHP is installed. For example:
C:\TMAS\PHP
3. In IIS, go to the Web Service Extensions. Add both versions’ ISAPI module separately to the extensions
list, and allow both.
4. In IIS, go to each website utilizing the PHP versions. Set an ISAPI filter if needed. On the Home Directory
tab, click Configuration, and add .php, .php3, .phtml, and any other extensions needed (perhaps .html?) to
be filtered through PHP, and specify the ISAPI module version needed for each website.
You can now run two versions of PHP. This is because the order of where to look for the .ini file changed
between previous PHP versions and PHP 5.2, as documented at http://us2.php.net/ini:
* SAPI module specific location (PHPIniDir directive in Apache 2, -c command line option in CGI and CLI, php_ini parameter in NSAPI, PHP_INI_PATH environment variable in THTTPD)
* The PHPRC environment variable. Before PHP 5.2.0 this was checked after the registry key mentioned below.
* HKEY_LOCAL_MACHINE\SOFTWARE\PHP\IniFilePath (Windows Registry location)
* Current working directory (for CLI)
* The web server’s directory (for SAPI modules), or directory of PHP (otherwise in Windows)
* Windows directory (C:\windows or C:\winnt) (for Windows), or —with-config-file-path compile time option
—————————————————-
PHP 5.2.9.2 Install on XP Pro IIS 5.1 — phpinfo( ) results incorrect
Testing Date: 05.15.09
Background:
For several days now I, as a newbie, have been unsure if I had installed PHP correctly, or not. No matter what I did phpinfo( ) reported «Configuratin File Path» as: “C:\WINDOWS”. I was left to wonder what was wrong.
To help resolve the phpinfo() “issue”, I conducted a series of tests using two scripts:
The first is “test-php-ini-loaded.php”; it is stored in c:\inetpub\wwwroot, and has the following code:
if ( $inipath ) <
echo ‘Loaded php.ini: ‘ . $inipath ;
> else <
echo ‘A php.ini file is not loaded’ ;
>
?>
The second script is simply calls phpinfo( ). It is named test.php, is stored in “c:\inetpub\wwroot”, and has the following code:
( ); ?>
My Dev Environment:
1. Windows XP Pro SP3
2. IIS 5.1 / MMC 3.0
3. PHP 5.2.9.2 – phpMyAdmin not yet installed
4. (plus MySQL 5.1, etc.)
5. Install location is on my local E: drive
Использование PHP в командной строке
Содержание
User Contributed Notes 35 notes
You can easily parse command line arguments into the $_GET variable by using the parse_str() function.
?>
It behaves exactly like you’d expect with cgi-php.
$ php -f somefile.php a=1 b[]=2 b[]=3
This will set $_GET[‘a’] to ‘1’ and $_GET[‘b’] to array(‘2’, ‘3’).
Even better, instead of putting that line in every file, take advantage of PHP’s auto_prepend_file directive. Put that line in its own file and set the auto_prepend_file directive in your cli-specific php.ini like so:
It will be automatically prepended to any PHP file run from the command line.
When you’re writing one line php scripts remember that ‘php://stdin’ is your friend. Here’s a simple program I use to format PHP code for inclusion on my blog:
UNIX:
cat test.php | php -r «print htmlentities(file_get_contents(‘php://stdin’));»
DOS/Windows:
type test.php | php -r «print htmlentities(file_get_contents(‘php://stdin’));»
I had a problem with the $argv values getting split up when they contained plus (+) signs. Be sure to use the CLI version, not CGI to get around it.
i use emacs in c-mode for editing. in 4.3, starting a cli script like so:
#!/usr/bin/php -q /* -*- c -*- */
— mode automatically when i loaded the file for editing . the ‘-q’ flag didn ‘t actually do anything (in the older cgi versions, it suppressed html output when the script was run) but it caused the commented mode line to be ignored by php.
in 5.2, ‘ — q ‘ has apparently been deprecated. replace it with ‘ — ‘ to achieve the 4.3 invocation-with-emacs-mode-line behavior:
#!/usr/bin/php — /* -*- c -*- */
t go back to your 4.3 system and replace ‘-q’ with ‘—‘ ; it seems to cause php to hang waiting on STDIN .
Just a note for people trying to use interactive mode from the commandline.
The purpose of interactive mode is to parse code snippits without actually leaving php, and it works like this:
[root@localhost php-4.3.4]# php -a
Interactive mode enabled
I noticed this somehow got ommited from the docs, hope it helps someone!
Parsing commandline argument GET String without changing the PHP script (linux shell):
URL: index.php?a=1&b=2
Result: output.html
echo «» | php -R ‘include(«index.php»);’ -B ‘parse_str($argv[1], $_GET);’ ‘a=1&b=2’ >output.html
(no need to change php.ini)
You can put this
echo «» | php -R ‘include(«‘$1′»);’ -B ‘parse_str($argv[1], $_GET);’ «$2»
in a bash script «php_get» to use it like this:
php_get index.php ‘a=1&b=2’ >output.html
or directed to text browser.
php_get index.php ‘a=1&b=2’ |w3m -T text/html
use » instead of ‘ on windows when using the cli version with -r
php -r «echo 1»
— correct
php -r ‘echo 1’
PHP Parse error: syntax error, unexpected »echo’ (T_ENCAPSED_AND_WHITESPACE), expecting end of file in Command line code on line 1
If you want to be interactive with the user and accept user input, all you need to do is read from stdin.
echo «Are you sure you want to do this? Type ‘yes’ to continue: » ;
$handle = fopen ( «php://stdin» , «r» );
$line = fgets ( $handle );
if( trim ( $line ) != ‘yes’ ) <
echo «ABORTING!\n» ;
exit;
>
echo «\n» ;
echo «Thank you, continuing. \n» ;
?>
Ok, I’ve had a heck of a time with PHP > 4.3.x and whether to use CLI vs CGI. The CGI version of 4.3.2 would return (in browser):
—
No input file specified.
—
And the CLI version would return:
—
500 Internal Server Error
—
It appears that in CGI mode, PHP looks at the environment variable PATH_TRANSLATED to determine the script to execute and ignores command line. That is why in the absensce of this environment variable, you get «No input file specified.» However, in CLI mode the HTTP headers are not printed. I believe this is intended behavior for both situations but creates a problem when you have a CGI wrapper that sends environment variables but passes the actual script name on the command line.
By modifying my CGI wrapper to create this PATH_TRANSLATED environment variable, it solved my problem, and I was able to run the CGI build of 4.3.2
Parsing command line: optimization is evil!
One thing all contributors on this page forgotten is that you can suround an argv with single or double quotes. So the join coupled together with the preg_match_all will always break that 🙂
Here is a proposal:
#!/usr/bin/php
( arguments ( $argv ));
function arguments ( $args )
<
array_shift ( $args );
$endofoptions = false ;
$ret = array
(
‘commands’ => array(),
‘options’ => array(),
‘flags’ => array(),
‘arguments’ => array(),
);
while ( $arg = array_shift ( $args ) )
<
// if we have reached end of options,
//we cast all remaining argvs as arguments
if ( $endofoptions )
<
$ret [ ‘arguments’ ][] = $arg ;
continue;
>
// Is it a command? (prefixed with —)
if ( substr ( $arg , 0 , 2 ) === ‘—‘ )
<
// is it the end of options flag?
if (!isset ( $arg [ 3 ]))
<
$endofoptions = true ;; // end of options;
continue;
>
$value = «» ;
$com = substr ( $arg , 2 );
// is it the syntax ‘—option=argument’?
if ( strpos ( $com , ‘=’ ))
list( $com , $value ) = split ( «=» , $com , 2 );
// is the option not followed by another option but by arguments
elseif ( strpos ( $args [ 0 ], ‘-‘ ) !== 0 )
<
while ( strpos ( $args [ 0 ], ‘-‘ ) !== 0 )
$value .= array_shift ( $args ). ‘ ‘ ;
$value = rtrim ( $value , ‘ ‘ );
>
$ret [ ‘options’ ][ $com ] = !empty( $value ) ? $value : true ;
continue;
// Is it a flag or a serial of flags? (prefixed with -)
if ( substr ( $arg , 0 , 1 ) === ‘-‘ )
<
for ( $i = 1 ; isset( $arg [ $i ]) ; $i ++)
$ret [ ‘flags’ ][] = $arg [ $i ];
continue;
>
// finally, it is not option, nor flag, nor argument
$ret [ ‘commands’ ][] = $arg ;
continue;
>
/* vim: set expandtab tabstop=2 shiftwidth=2: */
?>
If your php script doesn’t run with shebang (#!/usr/bin/php),
and it issues the beautifull and informative error message:
«Command not found.» just dos2unix yourscript.php
et voila.
If you still get the «Command not found.»
Just try to run it as ./myscript.php , with the «./»
if it works — it means your current directory is not in the executable search path.
If your php script doesn’t run with shebang (#/usr/bin/php),
and it issues the beautifull and informative message:
«Invalid null command.» it’s probably because the «!» is missing in the the shebang line (like what’s above) or something else in that area.
Just a variant of previous script to accept arguments with ‘=’ also
function arguments ( $argv ) <
$_ARG = array();
foreach ( $argv as $arg ) <
if ( ereg ( ‘—([^=]+)=(.*)’ , $arg , $reg )) <
$_ARG [ $reg [ 1 ]] = $reg [ 2 ];
> elseif( ereg ( ‘-([a-zA-Z0-9])’ , $arg , $reg )) <
$_ARG [ $reg [ 1 ]] = ‘true’ ;
>
>
return $_ARG ;
>
?>
$ php myscript.php —user=nobody —password=secret -p —access=»host=127.0.0.1 port=456″
Array
(
[user] => nobody
[password] => secret
[p] => true
[access] => host=127.0.0.1 port=456
)
Just another variant of previous script that group arguments doesn’t starts with ‘-‘ or ‘—‘
function arguments ( $argv ) <
$_ARG = array();
foreach ( $argv as $arg ) <
if ( ereg ( ‘—([^=]+)=(.*)’ , $arg , $reg )) <
$_ARG [ $reg [ 1 ]] = $reg [ 2 ];
> elseif( ereg ( ‘^-([a-zA-Z0-9])’ , $arg , $reg )) <
$_ARG [ $reg [ 1 ]] = ‘true’ ;
> else <
$_ARG [ ‘input’ ][]= $arg ;
>
>
return $_ARG ;
>
print_r ( arguments ( $argv ));
?>
$ php myscript.php —user=nobody /etc/apache2/*
Array
(
[input] => Array
(
[0] => myscript.php
[1] => /etc/apache2/apache2.conf
[2] => /etc/apache2/conf.d
[3] => /etc/apache2/envvars
[4] => /etc/apache2/httpd.conf
[5] => /etc/apache2/mods-available
[6] => /etc/apache2/mods-enabled
[7] => /etc/apache2/ports.conf
[8] => /etc/apache2/sites-available
[9] => /etc/apache2/sites-enabled
)
How to change current directory in PHP script to script’s directory when running it from command line using PHP 4.3.0?
(you’ll probably need to add this to older scripts when running them under PHP 4.3.0 for backwards compatibility)
Here’s what I am using:
chdir(preg_replace(‘/\\/[^\\/]+$/’,»»,$PHP_SELF));
Note: documentation says that «PHP_SELF» is not available in command-line PHP scripts. Though, it IS available. Probably this will be changed in future version, so don’t rely on this line of code.
Use $_SERVER[‘PHP_SELF’] instead of just $PHP_SELF if you have register_globals=Off
We can pass many arguments directly into the hashbang line.
As example many ini setting via the -d parameter of php.
—
#!/usr/bin/php -d memory_limit=2048M -d post_max_size=0
phpinfo();
exit;
—
./script | grep memory
memory_limit => 2048M => 2048M
—
But we can also use this behaviour into a second script, so it call the first as an interpreter, via the hashbang:
—
#!./script arg1 arg2 arg3
—
However the parameters are dispatched in a different way into $argv
All the parameters are in $argv[1], $argv[0] is the interpreter script name, and $argv[1] is the caller script name.
To get back the parameters into $argv, we can simply test if $argv[1] contains spaces, and then dispatch again as normal:
#!/usr/bin/php -d memory_limit=2048M -d post_max_size=0
( $argv );
if ( strpos ( $argv [ 1 ], ‘ ‘ ) !== false ) <
$argw = explode ( » » , $argv [ 1 ]);
array_unshift ( $argw , $argv [ 2 ]);
$argv = $argw ;
>
var_dump ( $argv ); ?>
—
array(3) <
[0]=>
string(8) «./script»
[1]=>
string(15) «arg1 arg2 arg3 »
[2]=>
string(14) «./other_script»
>
array(4) <
[0]=>
string(8) «./other_script»
[1]=>
string(4) «arg1»
[2]=>
string(4) «arg2»
[3]=>
string(4) «arg3»
>
—
This will maintain the same behaviour in all cases and allow to even double click a script to call both parameters of another script, and even make a full interpreter language layer. The other script doesn’t has to be php. Take care of paths.
Adding a pause() function to PHP waiting for any user input returning it:
function pause () <
$handle = fopen ( «php://stdin» , «r» );
do < $line = fgets ( $handle ); >while ( $line == » );
fclose ( $handle );
return $line ;
>
?>
This posting is not a php-only problem, but hopefully will save someone a few hours of headaches. Running on MacOS (although this could happen on any *nix I suppose), I was unable to get the script to execute without specifically envoking php from the command line:
[macg4:valencia/jobs] tim% test.php
./test.php: Command not found.
However, it worked just fine when php was envoked on the command line:
[macg4:valencia/jobs] tim% php test.php
Well, here we are. Now what?
Was file access mode set for executable? Yup.
[macg4:valencia/jobs] tim% ls -l
total 16
-rwxr-xr-x 1 tim staff 242 Feb 24 17:23 test.php
And you did, of course, remember to add the php command as the first line of your script, yeah? Of course.
#!/usr/bin/php
print «Well, here we are. Now what?\n» ; ?>
So why dudn’t it work? Well, like I said. on a Mac. but I also occasionally edit the files on my Windows portable (i.e. when I’m travelling and don’t have my trusty Mac available). Using, say, WordPad on Windows. and BBEdit on the Mac.
Aaahhh. in BBEdit check how the file is being saved! Mac? Unix? or Dos? Bingo. It had been saved as Dos format. Change it to Unix:
[macg4:valencia/jobs] tim% ./test.php
Well, here we are. Now what?
[macg4:valencia/jobs] tim%
NB: If you’re editing your php files on multiple platforms (i.e. Windows and Linux), make sure you double check the files are saved in a Unix format. those \r’s and \n’s ‘ll bite cha!
If you edit a php file in windows, upload and run it on linux with command line method. You may encounter a running problem probably like that:
[root@ItsCloud02 wsdl]# ./lnxcli.php
Extension ‘./lnxcli.php’ not present.
Or you may encounter some other strange problem.
Care the enter key. In windows environment, enter key generate two binary characters ‘0D0A’. But in Linux, enter key generate just only a ‘OA’.
I wish it can help someone if you are using windows to code php and run it as a command line program on linux.
Spawning php-win.exe as a child process to handle scripting in Windows applications has a few quirks (all having to do with pipes between Windows apps and console apps).
To do this in C++:
// We will run php.exe as a child process after creating
// two pipes and attaching them to stdin and stdout
// of the child process
// Define sa struct such that child inherits our handles
SECURITY_ATTRIBUTES sa = < sizeof(SECURITY_ATTRIBUTES) >;
sa.bInheritHandle = TRUE;
sa.lpSecurityDescriptor = NULL;
// Create the handles for our two pipes (two handles per pipe, one for each end)
// We will have one pipe for stdin, and one for stdout, each with a READ and WRITE end
HANDLE hStdoutRd, hStdoutWr, hStdinRd, hStdinWr;
// Now we have two pipes, we can create the process
// First, fill out the usage structs
STARTUPINFO si = < sizeof(STARTUPINFO) >;
PROCESS_INFORMATION pi;
si.dwFlags = STARTF_USESTDHANDLES;
si.hStdOutput = hStdoutWr;
si.hStdInput = hStdinRd;
// And finally, create the process
CreateProcess (NULL, «c:\\php\\php-win.exe», NULL, NULL, TRUE, NORMAL_PRIORITY_CLASS, NULL, NULL, &si, &pi);
// Close the handles we aren’t using
CloseHandle(hStdoutWr);
CloseHandle(hStdinRd);
// Now that we have the process running, we can start pushing PHP at it
WriteFile(hStdinWr, » echo ‘test’ ; ?> «, 9, &dwWritten, NULL);
// When we’re done writing to stdin, we close that pipe
CloseHandle(hStdinWr);
// Reading from stdout is only slightly more complicated
int i;
std::string processed(«»);
char buf[128];
For those of you who want the old CGI behaviour that changes to the actual directory of the script use:
chdir(dirname($_SERVER[‘argv’][0]));
at the beginning of your scripts.
an another «another variant» :
function arguments ( $argv )
<
$_ARG = array();
foreach ( $argv as $arg )
<
if ( preg_match ( ‘#^-<1,2>([a-zA-Z0-9]*)=?(.*)$#’ , $arg , $matches ))
<
$key = $matches [ 1 ];
switch ( $matches [ 2 ])
<
case » :
case ‘true’ :
$arg = true ;
break;
case ‘false’ :
$arg = false ;
break;
default:
$arg = $matches [ 2 ];
>
$_ARG [ $key ] = $arg ;
>
else
<
$_ARG [ ‘input’ ][] = $arg ;
>
>
return $_ARG ;
>
?>
$php myscript.php arg1 -arg2=val2 —arg3=arg3 -arg4 —arg5 -arg6=false
[arg2] => val2
[arg3] => arg3
[arg4] => true
[arg5] => true
[arg5] => false
)
You can also call the script from the command line after chmod’ing the file (ie: chmod 755 file.php).
On your first line of the file, enter «#!/usr/bin/php» (or to wherever your php executable is located). If you want to suppress the PHP headers, use the line of «#!/usr/bin/php -q» for your path.
One of the things I like about perl and vbscripts, is the fact that I can name a file e.g. ‘test.pl’ and just have to type ‘test, without the .pl extension’ on the windows command line and the command processor knows that it is a perl file and executes it using the perl command interpreter.
I did the same with the file extension .php3 (I will use php3 exclusivelly for command line php scripts, I’m doing this because my text editor VIM 6.3 already has the correct syntax highlighting for .php3 files ).
I modified the PATHEXT environment variable in Windows XP, from the » ‘system’ control panel applet->’Advanced’ tab->’Environment Variables’ button-> ‘System variables’ text area».
Then from control panel «Folder Options» applet-> ‘File Types’ tab, I added a new file extention (php3), using the button ‘New’ and typing php3 in the window that pops up.
Then in the ‘Details for php3 extention’ area I used the ‘Change’ button to look for the Php.exe executable so that the php3 file extentions are associated with the php executable.
You have to modify also the ‘PATH’ environment variable, pointing to the folder where the php executable is installed
Hope this is useful to somebody
To hand over the GET-variables in interactive mode like in HTTP-Mode (e.g. your URI is myprog.html?hugo=bla&bla=hugo), you have to call
php myprog.html ‘&hugo=bla&bla=hugo’
(two & instead of ? and &!)
There just a little difference in the $ARGC, $ARGV values, but I think this is in those cases not relevant.
dunno if this is on linux the same but on windows evertime
you send somthing to the console screen php is waiting for
the console to return. therefor if you send a lot of small
short amounts of text, the console is starting to be using
more cpu-cycles then php and thus slowing the script.
take a look at this sheme:
cpu-cycle:1 ->php: print(«a»);
cpu-cycle:2 ->cmd: output(«a»);
cpu-cycle:3 ->php: print(«b»);
cpu-cycle:4 ->cmd: output(«b»);
cpu-cycle:5 ->php: print(«c»);
cpu-cycle:6 ->cmd: output(«c»);
cpu-cylce:7 ->php: print(«d»);
cpu-cycle:8 ->cmd: output(«d»);
cpu-cylce:9 ->php: print(«e»);
cpu-cycle:0 ->cmd: output(«e»);
on the screen just appears «abcde». but if you write
your script this way it will be far more faster:
cpu-cycle:1 ->php: ob_start();
cpu-cycle:2 ->php: print(«abc»);
cpu-cycle:3 ->php: print(«de»);
cpu-cycle:4 ->php: $data = ob_get_contents();
cpu-cycle:5 ->php: ob_end_clean();
cpu-cycle:6 ->php: print($data);
cpu-cycle:7 ->cmd: output(«abcde»);
now this is just a small example but if you are writing an
app that is outputting a lot to the console, i.e. a text
based screen with frequent updates, then its much better
to first cach all output, and output is as one big chunk of
text instead of one char a the time.
ouput buffering is ideal for this. in my script i outputted
almost 4000chars of info and just by caching it first, it
speeded up by almost 400% and dropped cpu-usage.
because what is being displayed doesn’t matter, be it 2
chars or 40.0000 chars, just the call to output takes a
great deal of time. remeber that.
maybe someone can test if this is the same on unix-based
systems. it seems that the STDOUT stream just waits for
the console to report ready, before continueing execution.
