Recently I was stuck with one problem in linux configuration. I wanted to rsh to one machine A from other machine B but I was continuously getting “rcmd socket permission denied” error.

I installed Sendmail mail daemon in my linux machine. It took some time to configure the mail server. I was able to send mails to users using (as root),
mail –s “hi” username
data
.
I also can check the mail of the users using
mail –u username
But when I login to machine as that user I can not see any mails, I also noticed that id commands doesn’t return the use name, but also shows the id of the user.
>id
uid=3880 gid=124(e2m) groups=124(e2m),200(cvsusers)
I also checked that while login to system using username other …

TCL/TK is the very convient script language to create GUI on X-windows platform. Basically it wraps the call of X-Motif and allows user to create GUI very quickly without worry about X-motif functions..
Thought TCL is quite easy to use, it misses some useful functions. One of that is scrolling. Recently I was stuck-ed in similar problem. My requirement was to create a scrollable page with possibility to enter data by user.
Tcl/Tk only allows to attach scroll bar with Entry, Listbox and canvas widgets. If I use canvas then …

Useful Vi editor commands.
If you are using Unix then you must have used the VI editor for text edition. Vi Editor is the best editor in my view. If you have practiced enough and mastered the frequent command then you can understand its power.
I have summarized the basic commands and some useful command one should know to speed up VI editor use. I will not go in to details of how commands work.
There are mainly three modes of commands in VI editor, Insert mode, Command mode and colon mode. …