How to execute shell commands synchronously in PHP

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I need to run multiple scripts(5 scripts) via cmd, I want to make sure unless and until the first script finishes the second should not initiate. Thus after first script completes then only second should being then third one and so on.. Currently I am using the following code to do this

exec ("php phpscript1.php ");
exec ("php phpscript2.php ");
exec ("php phpscript3.php ");
exec ("php phpscript4.php ");
exec ("php phpscript5.php ");

I think these scripts run asynchronously, any suggestion guys so that these scripts can be run synchronously.

Answers

PHP exec will wait until the execution of the called program is finished, before processing the next line, unless you use & at the end of the string to run the program in background.

Saturday, December 3, 2022

yahya.bouchareb05-5f6383e056ff

The error data is output from the target program's STDERR stream. You can get access to the error data through the normal returned string from shell_exec() by appending 2>&1 to the command, which will redirect STDERR to STDOUT, the stream that you are currently seeing:

var_dump(shell_exec("ffmpeg -i /var/www/html/sitedomain/httpdocs/tmp/ebev1177.mp4 2>&1"));

You may also want to take a look at proc_open() which will allow you to get access to STDIN, STDOUT and STDERR as three individual streams, which can afford much finer grained control over the target program and exactly how you handle the input and output to it, including redirecting any and all of them directly to a log file if so desired. Be aware though that this is a much more complex mechanism with many pitfalls and tripping hazards.

More information on the standard streams can be found here.

Friday, December 2, 2022

shriyansh_gautam

Does your URL contain the & character? If so, your wget might be going into the background and shell_exec() might be returning right away.

For example, if $url is "http://www.example.com/?foo=1&bar=2", you would need to make sure that it is single-quoted when passed on a command line:

shell_exec("wget '$url'");

Otherwise the shell would misinterpret the &.

Escaping command line parameters is a good idea in general. The most comprehensive way to do this is with escapeshellarg():

shell_exec("wget ".escapeshellarg($url));

Friday, December 16, 2022

maxymoo

I never did this, but PHP Manual gave a link for PHP-Java Bridge for PHP5 as PHP/Java Bridge. If it is what you are looking for ?

Saturday, October 22, 2022

peque

The user contributions on the php.net have a write up on how to execute a stored procedure using the sqlsrv-prepare.

In case that is removed from the php.net user contributions in the future here is what it had(has) listed:

$procedure_params = array(
array(&$myparams['Item_ID'], SQLSRV_PARAM_OUT),
array(&$myparams['Item_Name'], SQLSRV_PARAM_OUT)
);
// EXEC the procedure, {call stp_Create_Item (@Item_ID = ?, @Item_Name = ?)} seems to fail with various errors in my experiments
$sql = "EXEC stp_Create_Item @Item_ID = ?, @Item_Name = ?";
$stmt = sqlsrv_prepare($conn, $sql, $procedure_params);

Here's the manual's page, http://php.net/manual/en/function.sqlsrv-prepare.php

Monday, October 24, 2022

buffalo

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How to execute shell commands synchronously in PHP

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