Please tell me what I am doing silly on my Debian Wheezy Raspberry Pi.
I have the following entry in my crontab
*/3 * * * * /home/pi/SocketClient
which, I hope, says that I want to run SocketClient from pi home directory every 3 minutes. It does not ever run.
If I run the bash script /home/pi/SocketClient from the command line it does what is expected and runs the commands it contains.
That script reads as follows
#!/bin/bash
/usr/bin/php /home/pi/SocketClient2.php

and if I run the "/usr/bin/php /home/pi/SocketClient2.php" from the command line it also works.
Both the script SocketClient as well as SocketClient2.php are executable and owned by user pi.

Hi there,

that looks a bit odd, because the 6th column in /etc/crontab should be the user with whose account the command is to be executed (typically root, but can be a regular user as well). Looks like you omitted that entirely.

On my Pi running here, I have just the default crontab with no extra cron jobs added, and it looks like that:

Maybe that's the point you're missing.

[X] Doc CPU

I tried
but it still fails. I tried both user pi as well as root.
I am running Raspbmc and I think that that is the issue for it works, as I had it set originally, on Raspbian.

Hi there,

that looks familiar to me.

I've never spent much attention to Raspbmc, but is this system using a cron daemon at all?
And I'm amazed that you say your initial sample worked on Raspbian, because I haven't yet seen a system without the user field in /etc/crontab - neither Debian, nor its derivatives Ubuntu and Mint, nor Gentoo, nor Raspbian. How would the cron daemon know which user to assign the cron job to? Would they all run as root?

I'm puzzled even more to find references on the net all showing crontab examples without the user field. Hmm...
By the way, have you tried to enable logging for cron and check the logs for information?

[X] Doc CPU

Thank you for your reply.
I have now implemented cron logging and have alter the command in my crontab to
The sudo -H is something I found on the web which I am told works.
I don't understand just what the -H is there for.
I have been given to understand that if one does not include the user in a crontab command line that command will run using the user/owner of crontab.
Therefore as my crontab is user pi crontab the contained commands will run for pi.

I forgot to say that despite altering the command in crontab it still does not work.

and all I see in /var/log/cron.log is
Jan 12 07:37:13 raspbmc crontab[19356]: (pi) BEGIN EDIT (pi)
Jan 12 07:37:40 raspbmc crontab[19356]: (pi) REPLACE (pi)
Jan 12 07:37:40 raspbmc crontab[19356]: (pi) END EDIT (pi)

which does not help at all. I know that I edited pi's crontab.

---------- Post added 01-12-15 at 01:21 PM ----------

I forgot to say that despite altering the command in crontab it still does not work.

and all I see in /var/log/cron.log is
Jan 12 07:37:13 raspbmc crontab[19356]: (pi) BEGIN EDIT (pi)
Jan 12 07:37:40 raspbmc crontab[19356]: (pi) REPLACE (pi)
Jan 12 07:37:40 raspbmc crontab[19356]: (pi) END EDIT (pi)

which does not help at all. I know that I edited pi's crontab.

cron was not running. It is usually the simplest is it not.