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Enter one or more of the following from a terminal (shell) prompt :-

# date set="2 OCT 2006 18:00:00"
# date -s "2 OCT 2006 18:00:00"
# date +%T -s "10:13:13"

See here for more examples

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Here is one way which also illustrates the use of the double backslash command substitution mechanism, whereby an embedded shell command in backquotes is replaced by the output of executing it :-

ls -lR `pwd`/* | grep 'epdfview'

The pwd command is expanded and replaced with the current working folder as the ls command is executed. In this example, the output is piped through the grep command to search for a file – this is for illustration, as you would normally do this with the find command as shown here.

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You can use the find command to do a wildcard search for files.
For example, the following will do a wild card name search :-

lynx / # find -name 'epdfview'
./home/mms/.config/epdfview
./usr/bin/epdfview
./usr/share/epdfview
lynx / #

The default is to search the current folder and all subfolders. You can search for a number of other fields as well as name, and there are lots of other options, see here

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This post details the installation I use for CVS based source control, together with some usage points and gotchas I came across. My preferred installation consists of the Eclipse CVS plugin and TortoiseCVS on the client side. This gives the flexibility of CVS access both inside and outside Eclipse. In my experience both CVS clients coexist well, and changes in one are immediately  reflected correctly in the other as would be expected. My server side consists of CVSNT running on a separate repository server.

I have broken this tutorial down into linked sub-posts as it was becoming too monolithic and covered multiple topics. The steps are as follows :-

1/ Server Installation using CVSNT

3/ Client Installation, Configuration and usage notes- TortoiseCVS

4/ Client Installation, Configuration and Usage notes – Eclipse CVS Plugin

5/ Branching and Merging in Eclipse CVS and TortoiseCVS

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See the Tomcat 6 Download Page

If you use the Windows service installer (self installing Exe) to install Tomcat 6.0.24 under Windows 7 64 bit, it insists on a 64 bit JVM. I am using a 32 bit JVM and if you try to use that, Tomcat will not start.

You can do this by using the 32 bit Windows zip version, which still allows you to run Tomcat as a service. It also allows you access to the Tomcat Configuration/Monitor utility which you can also run in the System Tray, but you have to set this up manually.

The following steps will do this install :-

1/ Download the 32 bit Zip installation above, and unzip to the desired target installation location.

2/ Edit <Tomcat Home>\conf\server.xml to change the default http port from 8080 if required

3/ Edit  <Tomcat Home>\conf\tomcat-users.xml to add an admin user if desired, by inserting the following in the <tomcat-users> section :-

<role rolename=”manager”/>
<role rolename=”admin”/>
<user name=”admin” password=”mypassword” roles=”manager,admin”/>

4/ Issue the command Service install from an administrator privileged command window pointing at the <Tomcat Home>\bin directory.

5/ Create the following shortcuts to run the Tomcat Configuration Utility and the System Tray Monitor Utility.
Substitute your device and directory for <Tomcat Home>.

Configuration Utility – Target:  “<Tomcat Home>\bin\tomcat6w.exe”  //ES//Tomcat6
System Tray Monitor – Target:  “<Tomcat Home>\bin\tomcat6w.exe”  //MS//Tomcat6
(Both Cases) – Start In: may be left blank
(Both cases) – Tick the Run as Administrator check box under either the Shortcut or compatibility tab.

6/ Note that you will have to OK running as administrator each time you run one of the shortcuts, assuming you have User Account Control turned on in Windows 7. This is also true if you try to run the tray monitor automatically in the startup group. Windows 7 insists that each time you log in, you have to OK the administrator usage(!) This is supposed to happen by adding such autostarted tray applications to a “blocked startup” group which have a tray icon to display and then selectively “OK” them to unblock them/OK the administrator usage. This never worked for me – anything I placed in the startup folder which needed administrator access just plain did not run at all, and I never saw this “blocked” icon. As it would mean OKing at each login anyway, it seemed to me that there is no point trying to autostart tray icons that need administrator access as it was more hassle to unblock them (even if it did work) rather than just run them as needed from the super bar or quick launch bar (and of course OK them).

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The process is a workaround for this eclipse bug, which seems to have been around for some time.

1. In Eclipse, enter Help/Add new software
2. Click the Add button to add a new update site, and enter the url https://ajax.dev.java.net/eclipse (I have also used http://ajax.dev.java.net/eclipse instead as suggested by other forums, but some users state that this does not work).
3. Wait for the screen to populate (this may take some time), then select “Glassfish Java EE 5 and Java EE 6 support” and hit next
4. Proceed with the installation as directed by the wizard.

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To set this up, I gave the designated user full permissions on the repository root, with full inheritance to all subfolders and files. I also made the user the owner, but this may not have been required. I also gave full access to the designated temp directory (the one set up in CVSNT admin) to this user.

When I tried to use a dedicated ‘limited’ (non administrator) account under windows XP pro I received the following error when I tried a checkout of CVSROOT :-

CVSNT user does not have read access to CVSROOT

Initially I thought this was an issue blocking all checkouts, as with the user set as an administrator, this checkout is allowed. However, the error only occurs on CVSROOT – all other operations on other modules appear to work normally. As CVSROOT is created internally by CVSNT as part of the repository, we should not be checking it out anyway so this should not be a problem.

Setting up this way minimises security issues especially when saving an explicit password parameter in TortoiseCVS (with the pserver protocol) to get around the lack of password caching.

The CVSNT admin utility, under the Server Settings tab, allows an anonymous user to be specified, allowing anonymous access from the clients. I did test this briefly, but could not get it to play ball with TortoiseCVS – tortoise always seemed to get demands for a password and gave an error if I tried anonymous access. I googled for answers to no avail – no info was available on this setting. I combed the documentation but this all seems to be aimed at the command line interface to CVS rather than the GUI control panel interface used in CVSNT.

My final solution therefore was to use an explicit limited (non administrator) account, which works fine.

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At the time of writing, the latest plugin version is 3.6.2. The zip of this version does not contain the installation instructions which were present in version 3.6.1, explaining how to download to a local repository and install from that within Eclipse.

The instructions may be found in ReadMe.pdf here.

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I had this issue when deleting and refetching a project from CVS into Eclipse.

It reported that it was unable to resolve a number of the persistence classes such as EntityManager and EntityManagerFactory, even though the libraries and the imports were all present correctly.

This was solved by removing the Java persistence facet from the project facets page, applying the change, and adding persistence back and reconfiguring it. The problem then disappeared.

This was one of several Eclipse ‘gotchas’ I have found where Eclipse reports errors which do not exist. Often, a reconfigure such as the above, or a restart/reload will sort it.

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Sometimes eclipse lists the following error in the problem view :-

Class xxx is listed in the persistence.xml file but is not mapped

This appears to be a synchronisation problem within Eclipse, as deleting the classes from persistence.xml and then adding them back by browsing with Eclipse’s own persistence.xml editor eliminates the problem, even though the resulting file is identical. Validating the original file did not solve the problem.

Even with the error listed, projects still run and build successfully, so the problem is not serious.

I have also had other cases where Eclipse has whinged about a perfectly good persistence.xml, and have in general just lived with it as it is not serious.

This is an important issue to be aware of though to prevent much head scratching when such a problem is believed to be a real error and is not!

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