no solution to timeout in fsockopen yet?

fazbob

Posted: Tue Jan 04, 2005 1:18 pm Post subject: no solution to timeout fsockopen bug YET???

salut forum!

i've been searching around for long for a solution to the problem that the function FSOCKOPEN() has when the server+port cannot be reachable, the coders who i expect will have an answer to this question know the problem very well i assume - so i wont go into the details of where the problem.... if you wanna know the details of this question plz check out the first post on http://www.sitepoint.com/forums/archive/index.php/t-39442

i am using php 4.1.2 on redHat linux 8 with Apache/1.3.22.

So to my REAL question.. isnt there any REAL solution to this issue? I have browsed too many forum posts looking for a solution:- and as DR_LaRRY_PEpPeR stresses this on a sitepoint thread: "the bug is in fsockopen() and theres NO WORK AROUND!!!" - in return VIRAL posted a possible 'work around' posted on phpbuilder by Michael Tanoviceanu (see last post of this page http://www.sitepoint.com/forums/archive/index.php/t-39442)--> which has a url for a patch on Patch is at: http://tanoviceanu.com/files/php_mysql.c.diff .. and, excited as i try to access this 'possible solution'.. the page cannot be accessed!!! so i just 😕

can anyone who knows a possible work around to doing port-scanning on a remote server - without using fsockopen (this is what i need to do: see if a certain service is off and notify the sysAdmin) help me out plz!

thanks coders!

nuff respek!
FaZ

tsinka

Hi,

do you have safe_mode enabled ? An alternative might be to use an external program like netcat.

The syntax for a verbose output with a timeout of 1 second is

netcat -v -w 1 -z hostname port

You only need the last line of output so use exec to call the command.

Example output:

successful:
hostname [ip address] port (port description) open

unsuccessfull:
hostname [ip address] port (port description) : No route to host
or
hostname [ip address] port (port description) : Connection timed out

You can then analyze the output if it contains e.g. open at the end.

netcat should be available on RedHat 8.

I think the bug has been fixed in some later version but if you don't want to update to a newer version then using e.g. netcat might be the best solution.

Thomas

tsinka

I forgot one important point. netcat prints the failure messages to stderr so you need to redirect stderr to stdout:

netcat -v -w 1 -z hostname port 2>&1

Thomas

Weedpacket

Noting the thread you linked to is four years old....

Searching for and locating this bug report in PHP's bug-tracking database (originally logged two months after the above Sitepoint thread started, and closed six moths after it ended)....

Observing that the code given in the bug report works fine for me on PHP versions 4.3 and 5....

Although there's nothing specifically on bug 13061 in the PHP [man]Changelog[/man] or the CVS Log for the relevant file, there has been almost complete rewrites of the function....

My suggestion would be to upgrade.

fazbob

Thank you for the suggestion to upgrade weedpacket.. and tSinka--> many thanks for letting me know about this netcat.. i havent used it but i will make sure it is of some use to me, even if it will not be useful in solving my current problems! :evilgrin: the question i have now is::- is it possible to embed code in my php scripts that use netcat functionality to 'improvise' the use of fsockopen? the commands u gave me show that this is a command prompt driven software- does this mean it has to be run externally?

i checked and noticed my php_info() shows safe_mode is enabled... i have across many forums mentioning that this affects fsockopen() with timeout from function properly- is this true? please explain to me (or forward me a link to some explanation on how safe_mode_enabled affects fsockopen() (and possibly fopen()...) BUT the server on which we are running our php web-apps is dedicated to us! this means we can have the safe_mode disabled ya? but what will be the implications of this?

in addition to the above paragraph-> this is how this whole scenario of wanting to use fsockopen() is laid out->

our php engine (with web-apps) is on server1, and an sms gateway (running on another of OUR dedicated servers) is on server2 (running JAVA, not PHP)... (so we always initiate connections FROM server1 TO server2)

i want to use fsockopen (or any other alternative) to check if a certain service on port X on server2 is available..

this is what confuses when we talk about safe_mode enabled =1/0 on server1 being the cause of fsockopen not working, isnt it supposed to be the other way round?? -> that is if server2 (the one that server1 is initiating a connection) is safe_enabled then the when server1 tries to use fsockopen() to connect it will be denied by server2?

thanks for ur help, and i will appreciate some more! 🙂

Faz