Unix Lab FAQs

To find your username, click on the following link and enter your Student ID or Last Name or First Name

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Your username will be listed under the ROCKS(Unix) system. Unix usernames are case sensitive.

Email the System's Administrator for your password.

The Unix server is ruby.rocks.uhcl.edu. You need to ssh to this server in order to access this account from outside UHCL. This server will not accept telnet connections.

You can download putty client which is a free ssh client.

At the command prompt, enter:

% passwd

The system will prompt you for the old password and then for the new password.

Go to the File tab and select the print option:

This is valid on both Ubuntu and Solaris 10 OS

• C & CPP
• Java

• C & CPP
• Java with Netbeans & Eclipse
• mySQL workbench

There are many ways of doing this:

If /usr/dt/bin is already added to your path, then at the command prompt enter:

% netscape

If /usr/dt/bin is not added to your path, then add it to your path and then at the command prompt enter:

%/usr/dt/bin/netscape

At the command prompt, enter:

% whatis name of the command

The system will return a brief decription of the command.

At the command prompt, enter:

% man name of the command

The system will return a detailed decription of the command. For example:

% man man

will give you the detailed description of the man command. To return to the prompt without reading the whole description, at the command prompt enter:

% <cntrl> c

At the command prompt, enter:

% uname

The system will return the current operating system. To find the version of the operating system, at the coommand prompt enter:

% uname -v

At the command prompt, enter:

% pwd

The system will return the path to you.

At the command prompt, enter:

% mkdir directory-name

At the command prompt, enter:

% cd path of the directory

By path of the directory, we mean the location of the directory from the root.

% cd d

At the command prompt, enter:

% cd ..

At the command prompt, enter:

% cd /

At the command prompt, enter:

% cd

First go into the directory to be emptied. Then, at the command prompt, enter:

% rm *

The system will inform you if there is another directory present in this directory. If so, at the command prompt enter:

% rmdir *

At the command prompt, enter:

% rmdir name of the directory

At the command prompt, enter one of the following commands:

% ls -R

To read the output of the system one page at a time, pipe the command to more. That is, at the command prompt , enter:

% name of the command | more

At the command prompt, enter:

% touch name of the file you would like to make

At the command prompt, enter:

% mv [old file name] [new file name]

At the command prompt, enter:

% cp [old file name] [new file name]

At the command prompt, enter:

% rm file name

At the command prompt, enter:

% ls

At the command prompt, enter:

% ls -a

This will list all files including the ones begining with a dot.

or

At the command prompt, enter:

% ls .*

This will list only the files beginning with a dot.

At the command prompt, enter:

% ls *_*

You can't - it isn't stored anywhere. Files have a last-modified time (shown by "ls -l"), a last-accessed time (shown by "ls -lu") and an inode change time (shown by "ls -lc"). The latter is often referred to as the "creation time" - even in some man pages - but that's wrong.

At the command prompt, enter:

% rm ./- filename

At the command prompt, enter:

%echo $PATH

Edit or create (if does not exist) .profile file in your home directory as follows:

% vi .profile

Add the following commands to the .profile file

PATH=$PATH: the name of the path that you wish to add
export PATH

Save .profile file as follows:

wq!

On many Sun hardware platforms, it is impossible to automatically detect the presence of a floppy in the drive. Run the command

/bin/volcheck

to ask volume management to check the floppy drive for media.

After volume management detects the floppy, it will be automatically mounted in

/floppy/< name_of_media >

The filemanager also has a menu item

File> Check for Floppy

which in effect, runs the volcheck command.

When formatting floppies,

fdformat

command will not put a file system on the floppy, by default. Use the

fdformat -d

flag to put a DOSfile system on it, or run the newfs command

newfs /vol/dev/rdiskette0/unnamed_floppy

to put a ufs file system on it.

First check is to see if volume management knows about it. The best way to check this is to look in /vol/dev/rdiskette0 and see if there is something there. If not, the volcheck command has not been run, or there is some hardware problem.

To start using vi, at the command prompt enter :

% vi filename

The filename can be the name of an existing file or the name of the file that you want to create.

For inserting press i and then start inserting.

To save the file and quit vi editor, first check that you are in command mode by pressing ESC and then enter:

:ZZ or :wq to both save and quit

or

:w to save file but not quit vi

or

:q! to quit

To quit vi without saving the contents of the buffer to the file press the ESC key and then enter

:q! .

ESC, [n] operator [m] object

:s/<char to be searched>/<new char>

To move to:

Next line down : j
Start on next line down : +
Previous line : k
Start of previous line : -
Left one character : h
Right one character : l
Go to first character of current line : ^
Go to last character of current line : $

To delete:

Current word : dw
Previous word : db
Entire line : dd
To end of line : d$

To insert:

Insert text after the cursor : a
Insert text before the cursor : i
Append text at the end of the current line : A
Insert text at the start of the current line : I
Open a new line below the current line : o
Open a new line above the current line : O

At the command prompt, enter:

% sqlplus

When entering your password, oracle needs to know which database it should connect to. The database that you use is known as the nas database. At the password prompt, enter:

% your-password@nas

Check the .login file in your c-shell. To do so, at the command prompt, enter:

% more . login

The ORACLE_BASE, ORACLE_HOME and the TWO_TASK environment variables need to be set to the following paths:

setenv ORACLE_BASE "/orasw/oracle"
setenv ORACLE_HOME "${ORACLE_BASE}/product/9.0.1/"
setenv TWO_TASK "nas"
setenv PATH "$PATH":${ORACLE_HOME}/bin

If the variables are not set, please edit the .login file and include the above 4 lines.Now you need to make sure that the changes go into effect. This can be accomplished by executing the following command:

% source .login

Now run the command SQLplus, and this should take care of it. If you STILL have a problem, copy a new .login file into your directory from /compilers/usrlib by entering the following command at the prompt:

% cp /compilers/usrlib/.login .

WARNING: You will lose all previous configurations made in the .login file.

Now source the .login file and it should work.

% source .login

If the source file is a C++ file, at the command prompt enter:

% g++ filename.cc –o filename

This will create the executable file named filename. If the source file is a C file,at the command prompt enter:

% g++ filename.c –o filename

This means that your PATH does not contain the directory that has gcc or g++ in it. /usr/local/bin is where the executables for gcc and g++ reside. You can either give the full path to gcc in the following manner:

% /usr/local/bin/gcc filename.cc –o filename

or add /usr/local/bin to your PATH

Your environment needs to have the LD_liBRARY_PATH set, so that it can find all its libraries. The LD_liBRARY_PATH has to be set in the .login file, for your program to execute correctly in the c-shell. Edit the .login file in your home directory and add the following into it.

setenv LD_liBRARY_PATH /compilers/SUNWspro/lib:/usr/local/lib:/usr/ openwin/lib

Now, source the .login file.

% source .login

Your account now points to the correct libraries that C and C++ requires.

The GNU Project Home page is located at:

www.fsf.org/home.htm

The GNU software documentation pages are located at:

http://www.delorie.com/gnu/docs

GNU links to Free Software Site Pages can be found at:

http://www.fsf.org/links.html#FreeSoftwareDocumentation

At the command prompt enter:

% javac filename.java -o filename

This will create the object file filename. Now execute the command

java -classpath .filename

This will execute the file named filename

You need to have the following variables set in your environment.

JAVA_HOME=/compilers/j2sdk1_3_1
J2EE_HOME=/usr/local/j2sdkee1.2.1
CLASSPATH=/faculty/abeyseke:/usr/local/j2sdkee1.2.1/lib/j2ee.jar:/compilers
/j2sdk1_3_1/lib/emailmessages.jar:/compilers/j2sdk1_3_1/lib/mm.mysql-2.0.4-bin.jar

Your also need to have the following included in your PATH variable:

/compilers/j2sdk1_3_1/bin:/usr/local/j2sdkee1.2.1/bin

When compiling the program, make sure that the -lpthread option is added to the gcc or g++ command. If this is omitted, the program still compiles successfully, but you will not be able to actually execute the program.

A request has to be made, by the instructor to the systems adminstrator, on your behalf, in order for you to get web account. It should be required for a course that you are taking. If the request is approved, your instructor will be notified of your account information.

Your web page is created on ruby.rocks.uhcl.edu. Your URL will be http://ruby.rocks.uhcl.edu/username

A directory will be created for the user at /usr/local/apache/cgi-bin , where all your CGI applicaitons can be stored. Please note that this is ONLY on the machined named Ruby, not on any machines in the lab.

A directory will be created for the user at /compilers/jakarta-tomcat-3.2.3/webapps, where all your TOMCAT files can be stored.

The TOMCAT installation on the system can be viewed at http://Ruby.rocks.uhcl.edu:8080. Your TOMCAT files can be stored at /compilers/jakarta-tomcat-3.2.3/webapps/username and can be viewed at http://Ruby.rocks.uhcl.edu:8080/username

A directory will be created for users at /compilers/jakarta-tomcat-3.2.3/classes/username to save their classes files.

At the command prompt, enter:

% echo $shell

In general, you can't, at least not without making special arrangements. When a child process is created, it inherits a copy of its parent's variables (and current directory). The child can change these values all it wants but the changes won't affect the parent shell, since the child is changing a copy of the original data.

Some special arrangements are possible. Your child process could write out the changed variables, if the parent was prepared to read the output and interpret it as commands to set its own variables.

Also, shells can arrange to run other shell scripts in the context of the current shell, rather than in a child process, so that changes will affect the original shell.

For instance, if you have a C shell script named "myscript":

cd /very/long/path
setenv PATH /something:/something-else

or the equivalent Bourne or Korn shell script

cd /very/long/path
PATH=/something:/something-else export PATH

and try to run "myscript" from your shell, your shell will fork and run the shell script in a subprocess. The subprocess is also running the shell; when it sees the "cd" command it changes *its* current directory, and when it sees the "setenv" command it changes *its* environment, but neither has any effect on the current directory of the shell at which you're typing (your login shell, let's say).

In order to get your login shell to execute the script (without forking) you have to use the "." command (for the Bourne or Korn shells) or the "source" command (for the C shell). I.e. you type

. myscript

to the Bourne or Korn shells, or

source myscript

to the C shell.

If all you are trying to do is change directory or set an environment variable, it will probably be simpler to use a C shell alias or Bourne/Korn shell function. See the "how do I get the current directory into my prompt" section of this article for some examples.

The answer depends on your Unix version (or rather on the kind of "echo" program that is available on your machine). A BSD-like "echo" uses the "-n" option for suppressing the final newline and does not understand the octal \nnn notation. Thus the command is:

% echo -n '^G'

where ^G means a _literal_ BEL-character (you can produce this in emacs using "Ctrl-Q Ctrl-G" and in vi using "Ctrl-V Ctrl-G")

A SysV-like "echo" understands the \nnn notation and uses \c to suppress the final newline, so the answer is:

echo '\007\c'

In sh, use read. It is most common to use a loop like:

while read line
do
...
done

Unfortunately csh has no way of distinguishing between a blank line and an end-of-file.

If you're using sh and want to read a *single* character from the terminal, you can try something like:

echo -n "Enter a character: "
stty cbreak # or stty raw readchar=`dd
if=/dev/tty bs=1 count=1 2>/dev/null`
stty -cbreak echo "

Let us first assume you are on a UNIX variant (e.g. 4.3BSD or SunOS) that knows about so-called `executable shell scripts'. Such a script must start with a line like:

#!/bin/sh

The script is called `executable' because just like a real (binary) executable it starts with a so-called `magic number' indicating the type of the executable. In our case this number is `#!' and the OS takes the rest of the first line as the interpreter for the script, possibly followed by 1 initial option like:

#!/bin/sed -f

Suppose this script is called `foo' and is found in /bin, then if you type:

foo arg1 arg2 arg3

the OS will rearrange things as though you had typed:

/bin/sed -f /bin/foo arg1 arg2 arg3

There is one difference though: if the setuid permission bit for `foo' is set, it will be honored in the first form of the command; if you really type the second form, the OS will honor the permission bits of /bin/sed, which is not setuid, of course.

If you are sure the number of arguments is at most 9, you can use:

eval last=\${$#}

In POSIX-compatible shells it works for ANY number of arguments. The following works always too:

for last
do
:
done

This can be generalized as follows:

for i
do
third_last=$second_last
second_last=$last
last=$i
done

Now suppose you want to REMOVE the last argument from the list, or REVERSE the argument list, or ACCESS the N-th argument directly, whatever N may be. Here is a basis of how to do it, using only built-in shell constructs, without creating subprocesses:

t0= u0= rest='1 2 3 4 5 6 7 8 9' argv=

for h in '' $rest
do
for t in "$t0" $rest
do
for u in $u0 $rest
do
case $# in
0)
break 3
esac
eval argv$h$t$u=\$1
argv="$argv \"\$argv$h$t$u\"" # (1)
shift
done
u0=0
done
t0=0
done

# now restore the arguments

eval set x "$argv" # (2)
shift

This example works for the first 999 arguments. Enough? Take a good look at the lines marked (1) and (2) and convince yourself that the original arguments are restored indeed, no matter what funny characters they contain!

To find the N-th argument now you can use this:

eval argN=\$argv$N

To reverse the arguments the line marked (1) must be changed to:

argv="\"\$argv$h$t$u\" $argv"

If you allow subprocesses as well, possibly executing nonbuilt-in commands, the `argvN' variables can be set up more easily:

N=1

for i
do
eval argv$N=\$i
N=`expr $N + 1`
done

To reverse the arguments there is still a simpler method, that even does not create subprocesses. This approach can also be taken if you want to delete e.g. the last argument, but in that case you cannot refer directly to the N-th argument any more, because the `argvN' variables are set up in reverse order:

argv=

for i
do
eval argv$#=\$i
argv="\"\$argv$#\" $argv"
shift
done

eval set x "$argv"
shift

Common LISP(CLISP) is installed on the server. The following is the path for CLISP to be added to PATH variable

/opt/csw/bin

Note : Please refer The Unix Path for more details on how to add PATH variable.