General :: Bash Script Variable NULL Instead Of Value Of Expression?
Nov 17, 2010Quote:
#!/bin/sh
for i in {1..10}
do
for j in {1..50}
[code]....
The first echo generates something like: abc.de.fgh The second echo generates:
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General :: Bash - HISTSIZE - Readonly Variable -bash - HISTFILESIZE - Readonly Variable
Dec 8, 2009On one of my servers I see this when I log in. What does this mean and how can I get it to go away? Everything seems to work fine, but none of my other machines give this error.
View 5 Replies View RelatedProgramming :: Null Pointer In Bash?
May 19, 2011#!/bin/bash
sed -n 8p file.txt
returns the 8th line to the StdOut.
If I assign the value to the variable line = $(sed -n 8p file.txt)
and now print it out with echo
echo $line
the line would be printed.
But what if the file has only 4 lines. What value would be assigned to the variable line?
I want to know that because I want to only print it if the value is "something", that is not null.
In Java for example I would do it like this...
String line = "";
line = reader.readLine(); // or anything else..
if(line!=null){
System.out.println(line);
}
How would I check if the value is not "null"(I don't know if bash knows null)
Programming :: Bash - Read Content Of File To Variable And Use This Variable In For Loop ?
Aug 21, 2009I'm trying to read content of file to variable and use this variable in for loop. The problem is, when I have c++ comment style in file - /*. Spaces in line are also interpreted as separated lines.
For example:
Code:
Changing $files to "$files" eliminate these problems but causes that whole content of variable is treated as one string (one execution of loop).
Software :: Get Variable From Text File Into Bash Variable?
Jun 10, 2009I have a text file i that has a mailTo: NAME in it. In a bash script i need to extract NAME and put it in a $variable to use. How do i do this?
View 2 Replies View RelatedProgramming :: Bash - Expression Is Always Evaluating To True
Jun 7, 2011This line if [[ $hamachi_reachable = true && $lan_reachable = true ]]; then is always evaluating to true. I gave two ips that are not valid, so that both variables would become false yet the whole expression is evaluating as true. With that set -x in there, I get this output.
Where am I going wrong?
Code:
Server :: Kernel Panic - WARNING: Can't Access (null) Exec Of Init ((null)) Failed
Aug 5, 2010I have a server running Red Hat Enterprise Linux ES (2.6.9.55.ELsmp). When it starts up I get the following error: Uncompressing Linux... Ok, booting the kernel. Red Hat nash version 4.2.1.10 starting WARNING: can't access (null) exec of init ((null)) failed!!!: 14 unmount /initrd/dev failed: 2 Kernel panic - not syncing: Attempted to kill init!
After that I got no response from the OS. I have the installation CD, so I tried to start the rescue mode, while going through the steps I received an error stating that mounting to /mnt/sysimage failed and that if I want to I can access a shell. I really don't know what to do from here
General :: Get N-variable Parameters In Bash
Mar 21, 2011I've a script that it's invoked with n-variable parameters. Here's an examples:
Code:
./myprogram.sh inputdir FIELD1 FIELD2 ... FIELDN outputfile In the script I would like to get the FIELD names that were passed.
General :: Substitute Variable In Bash
Mar 21, 2011 Assume that i a having the following three lines in an executable file
#/bin/bash
a=Tue
Tue=1
When i give echo $a the value should be 1, how to do this.
Programming :: Bash Script: Catch File Not Found Error And Send To /dev/null
Apr 21, 2010I have the following working script. It checks the directory for txt files, if files are there, it copies to another directory or gives error. I would like to exclude "file not found" errors and send them to /dev/null. All other errors should go to the email address as usual.
Code:
#!/bin/bash
function err
{
if [[ $? -ne 0 ]]
[Code]....
Programming :: Bash - Syntax For ((<arithmetic Expression>)) Usage ?
Mar 18, 2010I do not understand bash' syntax regarding the use of ((<arithmetic expression>)). $((<arithmetic expression>)) is tokenised to a single word. OK.
Code:
In isolation
Code:
It may not be used where a word is expected. This generates a syntax error. Why?
Code:
General :: Bash: Input Password Into A Variable?
Aug 22, 2010I'm basically setting up two sshfs mounts and I have it set up so I run one command but type my password twice.Is there an easy to way to input a password using bash and pass that variable to another process asking for a password?
View 5 Replies View RelatedGeneral :: Bash Variable As Parameter To Script?
May 10, 2011I want to create a variable that when passed as a parameter to another bash script will keep its string quotes (so it stays as one parameter). What ways can I achieve this cleanly?
Code:
john@ubuntu:/usr/local/src$ cat foo.sh
#!/bin/bash
echo $0
[code]....
General :: Concatenate Variable Names In Bash?
Apr 7, 2011In my script, and I would like to concatenate 2 variables names, to give me the true variable.I've 3 variables X1, X2 and X3, and I invoked them inside a for loop.
Code:
#!/bin/bash
X1=HELLO
[code]....
General :: Reading File Into Variable In Bash?
Mar 21, 2011I know that cat can output the file, but how do you store that output in a variable to process:
Code:
CONTENT=cat file.txt
This doesn't seem to work?
General :: Bash Catching The Function Returning Value Into A Variable?
Mar 17, 2010i am dealing with this problemI have a function
function Une {
...
return $some_variable
[code]...
General :: Bash Script - Forget Global Variable's Value?
Apr 9, 2011I have a hard time with my bash script.
It forget global variable's value.
First look at my script.
Code:
Echo "PKGS is [$PKGS] in after loop"
And data file for it is below. Let's name as list.txt
Code:
As you see, PKGS variable in loop has correct value.
However, after loop I can not get proper value for it.
General :: Simple Bash Command Causing Bad Variable Name
Feb 18, 2010When I run this command from shell, it runs ok
export REVS=`svn info svn+ssh://svn.myone.ca/var/svn/story/trunk/lib |grep 'Last Changed Rev:'| awk -F: '{print $2}'`
However when I save it into a file called test.sh (of course, I chmod it with +x), I got error "export: 2: bad variable name"
Here is the file:
#!/bin/bash
export REVS=`svn info svn+ssh://svn.myone.ca/var/svn/story/trunk/lib |grep 'Last Changed Rev:'| awk -F: '{print $2}'`
I am using ubuntu.
General :: Environmental Variable In Bash Command String?
Feb 9, 2011I do this:
Code:
a@b:~$ export A=hi
a@b:~$ echo $A
hi
a@b:~$ bash -c "export A=blah; echo $A"
hi
a@b:~$
Why doesn't the bash command print the new value of $A? Is there a way to make it do so?
General :: Pull String From A File Into A Variable Using Bash
Aug 6, 2011I have a file (.tmpfile) and inside it is a string which i only know part of, the rest being a random group of characters... I would like to know how to pull the whole string out of the file and into a variable.
View 13 Replies View RelatedProgramming :: Reading A Bash Variable In Bash Scripting ?
Nov 26, 2008I have a config file that contains:
my.config:
Code:
Now in my bash script, I want to get the output /home/user instead of $HOME once read. So far, I have managed to get the $HOME variable but I can't get it to echo the variable. All I get is the output $HOME.
Here is my parse_cmd script:
Code:
General :: Bash: Substitute Parameter In A Quoted String - Stored In Another Variable
Jan 31, 2010(variable substitution?)
(parameter expansion?)
Code:
run_repeatedly()
{
NUM=0
while [ <irrelevant stuff here> ]
[Code]....
run_repeatedly "programX -o "./messy/path/output-$NUM.txt"" The echo inside the loop prints "...-$NUM.txt"; obviously I'm aiming to have bash substitute the iteration number so that I end up with many output files not 1.
General :: Bash Variable Naming The Server - Monitor Trunk Failure?
May 30, 2010I'm writing a script for asterisk to monitor trunk failure, i do a loop for every trunk it got nad would like to name variable like server1=, server2= naming the server upgoing as the trunk is. here is the scripts:
[Code]....
what i would like to do is name the variable server, username and status with the count variable, like this server$COUNT to have server1 when on trunk one, bu as soon as i add the $COUNT after the server, it seems to try to make it a command, it says that:
Code:
./test.sh: line 45: server1=74.63.41.218: command not found
General :: Bash Variable - Simple Script For Finding And Copying Files Powered By The Command?
Aug 2, 2009Ive been using linux for a while but I am just getting into shell scripting, im currently trying to get a simple script for finding and copying files powered by the command:
Code:
This works fine from the command line but when put in a script such as:
Code:
Code:
with the keyboard inputs for $fc1 and $fc2 being *.doc and ~/test respectivly. The only problem i can see is the xargs -ivar "var" part possibly needing $var to be defined?
Ubuntu :: Mapping HAL's .fdi Expression To Xorg Expression?
Oct 6, 2010I want to translate this .fdi clause
Quote:
<match key="info.product" string="PS/2 Generic Mouse">
<merge key="input.x11_options.EmulateWheel" type="string">true</merge>
<merge key="input.x11_options.EmulateWheelButton" type="string">2</merge>[code].....
into its Xorg equivalent. What does it look like?
General :: Assign An "here Documents" Section To A Variable In Bash?
Mar 11, 2011Is it possible to assign an "here documents" section to a variable in bash?I would like to assign the following to a variable:
Code:
<html>
<body>
<p>THis is a test</p>
</body>
</html>
General :: Bash Script: Use The Directory Of The Script File As Variable?
Jan 16, 2010i'm not actually using Linux but i figured this might be the right place nonetheless..o i've got this little script file to compile and run some Java code:
Code:
#!/bin/bash
cd /Users/acid/Desktop/javaTest
[code]...
Ubuntu :: Bash Variable And /bin?
Mar 28, 2010I'm making a script I want to be able to just call (ie, rclick instead of ./rclick) where do I put it?
~/bin?
/bin?
/usr/bin?
Also, how do I pass a variable to the script (rclick 10 will rightclick 10 times) (Found, so simple... $1)Lastly, can I force it to run on CPU2? CPU1 is completley locked up if I run this on it... Or can I make it use less cpu cycles?
Programming :: Sed A Variable In Bash?
Mar 25, 2011I have beat this enough and don't get what should have been a very simple thing to do. I build a variable;
Code:
CLIST=java,lua,python,php,perl,ruby,tcl
CLIST will be used by another bash script but I need to replace the commas with a space. I
[code]...
Programming :: Variable Substitution In BASH?
Feb 17, 2011Just a simple BASH for loop to read the file path from a text file (clean.txt) echo the variable for debug purposes, and scp it to a server I have using port 50 for SSH.
I've already formatted the entries in clean.txt to handle spaces correctly, using sed replacement.
Example from the clean.txt file:
Code:
/MP3/NAS000000001/Barenaked Ladies/Barenaked Ladies - Barenaked For The Holidays/20 Auld Lang Syne.mp3
/MP3/NAS000000001/Barenaked Ladies/Barenaked Ladies - Barenaked For The Holidays/14 Deck the Stills.mp3
[Code]....
