Programming :: Using Variable In A Command?

Apr 14, 2011

i'm trying to execute a shell script, i'm trying to use the values in an array for use in a sed command:

sed -n '/Sales ID: ${array[$i]}/,/Totals:/p'

that command creates empty files. so my guess is that its not recognizing the array as an array but as text?
how would i be able to utilize the array in the command? i got it, didnt think that if i doubled up the single quotes that it would work, but this worked:

sed -n '/Sales ID: '${array[$i]'}/,/Totals:/p'

View 4 Replies


ADVERTISEMENT

Programming :: Calling Command From History Using Variable Like !$command?

Nov 19, 2008

suppose i store the history number of a command say :

1004 cat file

Then now i want to run it like : !1004 but by using a variable.

command=1004
!$command

i am getting errors like :

command=1004command

View 2 Replies View Related

Programming :: Store A Command In A Variable?

Jan 28, 2010

Code:

ls Again the command can be stored in a variable and then executed. Like

Code:

var=ls
&var

The above two codes are the same. The problem occurs when we try to pipeline it. Consider the following problem:

Code:

ls | grep *

works fine...but when we try to store it in a variable and run the command there is an error.

Code:

var="ls|grep *"
$var

how to store this kind of commands in a variable?

View 11 Replies View Related

Programming :: Change Variable In Case Command?

Aug 7, 2010

I want to display 4 options using the case command and refresh the screen when options 1 and 2 are chosen (no changes to the options and you get asked again to chose option), but give a message for option 3 and exit on option 4. I set this up with the script below, but choosing option 1 works and choosing option 2 exits the script.

Code:

#!/bin/bash
#testing options
Option="0"

[code]....

View 7 Replies View Related

Programming :: Pass A Shell Variable To An AWK Command?

Dec 23, 2010

I have the following code :

Code:
E_BADARGS=65
if [ $# -ne 2 ] ; then

[code]...

View 1 Replies View Related

Programming :: Assigning Bash Variable With The System Command In Awk?

Mar 1, 2011

I am having all sorts of trouble trying to assign a variable within an awk script with the system command. I know there is a lot of ways around this problem, but for efficiency reasons, I would like to, within my awk script, do something like

system(x=3)

or

system(x=NR)

and, latter on the shell script which calls the awk script, use the variable $x. But nothing is passed to x. I have already tried things like

command = "x=3"
system(command)

and also used a pipeline within the system to pipe it to /bin/sh In fact tried a lot of stuff like that, using $(( )) etc etc etc I can create directories e write to files (yes, i could write to a file and read from there, but I dont think it is efficient, plus I am puzzled).

View 7 Replies View Related

Programming :: Put A Variable In The $PS1 Prompt That Will Change Each Time A Command Is Run?

Feb 11, 2011

I would like to put a variable in the $PS1 prompt that will change each time a command is run. I want the color of the $PS1 prompt to change each time a command is run.I know that I can do this:

Code:
PS1="h@w # "
## "#" is changes every time a command is run

[code]....

View 9 Replies View Related

Programming :: Receive Command Output And Store It To A Variable?

Apr 3, 2010

Suppose I want to account number of files beginning with abc , I can use "ls 'abc* | grep abc | wc -l", this will return me a number.
I want to store this number in a variable, say var1, so I tried
1. "ls 'abc* | grep abc | wc -l |read var1", but this didn't work as var1 has no value somehow.
2. var1='ls 'abc* | grep abc | wc -l', this just assign the entire string "ls 'abc* | grep abc | wc -l" to var1, which is not I wanted.

I don't want to store the value to a temporary file and then read the value from that file. I think there should be a direct way to get the value, but don't know how. I know in tcsh, one can just use set var1='ls 'abc* | grep abc | wc -l', but it also doesn't work in bash. Can anyone give any clue about this?

View 5 Replies View Related

Programming :: Pass An Expect Command Result Into A Variable And Then Use It Again?

May 4, 2010

I'm trying to create a program that would locate the oldest file of a certain type on a server. Here's the commands:

OLDEST_PATH=`find -L / -depth -maxdepth 6 -mindepth 6 -type d | sort -f | head -1`
OLDEST_FILE=`find -L $OLDEST_PATH | grep .mp3 | sort -f | head -1`
ls -al $OLDEST_FILE

I'm writing this all in expect but I'm having problems. The main problem I have is whenever I try to run the first command, I can't seem to isolate the result of the OLDEST_PATH so that the 2nd command will work. There always seems to be a newline in the variable and the result is only "find -L" command running and it bypasses the variable. If I can just figure out how to get the 1st and 2nd command to work, then I can figure out the 3rd. Here's some code:

Code:
send "find -L / -depth -maxdepth 6 -mindepth 6 -type d | sort -f | head -1
"
sleep 20
expect -re "(.*)

[Code]....

I know there is a better way to write this. I've tried multiple ways and this just happens to be the last way I've tried it. If you try running this, you'll notice that there is still carriage returns after the result of OLDEST_PATH and it prevents the 2nd "find" command from working properly.

View 2 Replies View Related

Programming :: Using Variable To Store Command Lines In A Pipeline?

Jan 28, 2010

Was trying to write a shell script that has if conditional statements to decide different arguments for a command.Basically:

Code:
if [ "$1" = 1 ]
then

[code]...

View 6 Replies View Related

Programming :: Variable Substitution In Sqlite Open Db Command?

Jun 15, 2010

I have the following TCL code:

if{ [catch {sqlite3 db /path/to/db/file} result] } {
puts stderr $result
} else {
do something
}

What I want is to use a variable for the file name/path. When I put in a variable instead of the absolute path, I get an error: "missing close-brace: possible unbalanced brace in comment while executing"

This is weird because when I run the code with the fully qualified pathname, it works fine. I substitute out the pathname for a variable containing the pathname ($variable) and I get this error.

View 1 Replies View Related

Programming :: Bash Script: Assign Command Ouput To A Variable Without Executing It?

Feb 12, 2011

I'm trying to execute the following command within a bash script:

Code:
tac /var/log/system.log | head -1
The script I wrote is:

[code]...

View 1 Replies View Related

Programming :: Bash - Read Content Of File To Variable And Use This Variable In For Loop ?

Aug 21, 2009

I'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).

View 6 Replies View Related

Programming :: Make A New Variable With The String From The Old Variable Btut Without Any Plus Sign?

Apr 7, 2010

my script has a variable which comes in the form +00.00 +0.00 -00.00 or -0.00 (the numbers can be any in that form) for any that have a + symbol I need to remove the +, but if it has a - symbol it needs to stay.

i need to make a new variable with the string from the old variable btut without any plus sign. I have tried a lot of different ways with no success, each thing I tried either left the + or removed the entire string. I think this should work but doesn't

foo=+12.40
bar=${foo#+}

View 4 Replies View Related

Programming :: Search Within A Variable And Assign The Results To A New Variable?

Apr 25, 2011

how I can search within a variable and assign the results to a new variable. I'll use the following as an example -

cars="Audi BMW Cadillac Chevy Dodge Ferrari Ford Mercedes"
list=`echo ${cars} | egrep -o '<A?+|<C+'`

with the echo command I get the following output assigned to list -

A
C
C

What I'd like to get for output is -

Audi
Cadillac
Chevy

how I could do this regardless of upper/lower case letters?

View 5 Replies View Related

Programming :: Storing Output Of "time" Command To A Variable

Jan 21, 2011

In my script, I need to get execution time of a command (say 'ls') in mili seconds level. For this i tried using "time" command to retrieve the total execution time in milli seconds. But, the problem is that, how to save the output of time command in a variable. The format of the command is like "time ls -R /opt" Going further, the o/p of 'time' command is:

real 0m0.003s
user 0m0.004s
sys 0m0.000s

Here, in my script, I would like to use only middle line "user 0m0.004s" saved to the variable but unable to find out the way.

View 1 Replies View Related

Programming :: Assign Value Of C Variable To Shell Variable?

Apr 28, 2010

included shell script inside c program, and i wanted to assign the value of c variable to shell variable..Can any one please suggest me how to do it?

View 8 Replies View Related

Programming :: Assignment To A Variable Variable?

Mar 17, 2011

This loop is part of a bash script which takes multiple arguments.

Code:
for ((i=1;i<=$number;++i)) ; do
offset=$(($i+5))

[code]...

View 3 Replies View Related

Programming :: Pass Variable In Mysql Qyery In C Programming?

Dec 4, 2010

i want to pass variable in mysql qyery in c programming

View 1 Replies View Related

Red Hat / Fedora :: Assign A Variable To A Command?

Sep 10, 2010

I can print a specific line of a file with:$ sed -n '20p' myFileHow can I store it in a variable (in a shell script)?(I wasn't successful with "myVar=sed -n '20p' myFile" for example)

View 2 Replies View Related

Software :: Scripting : Using A Variable In A Command?

Jan 13, 2009

I need to create a zip file of jpg and bmp files. The zip file is named after the first file it finds which ends with .dat. Here is my script:

Code:

DAT_FILE= `find . -maxdepth 1 -iname "*.dat" | head -1 | sed 's/..(.*)..../1/'`
(cd pics; find . ( -name "*.bmp" -o -name "*.jpg" ) -print | zip ../$DAT_FILE -@ )

BTW my sed command cut off the first two chars and last four chars since find will return the filename is the form of "./filename.dat" and I just want to extract filename. When I run this script, it creates a zip file named ".zip". How do I fix this so the zip file is named after my dat file?

View 3 Replies View Related

SUSE :: How To Fix $PATH Variable - Command Not Found

Dec 20, 2010

I tried to install JRE to my remote Suse 11 SP1 linux.After i finished with files i typed like

export PATH=<my jre path>

now i have no bash commands - typing ls causes

-bash: ls: command not found

i think that i should re-export my PATH to the right value but i don't know what it should be. I tried differend values

/etc/profile
/usr/bin

View 3 Replies View Related

General :: Better To Use 'at' Command Instead Of Time Variable In Shutdown?

Apr 20, 2010

I was reading that if I want to do a one time scheduled command, I should use at, which I've never done, as opposed to cron, which i'm kinda familiar with. But what I want to do is reboot my server at 3am tomorrow and force it to check the file systems with a shutdown -rF. For this do I even need to use "at" or could I just say shutdown -rF 3:00.Will that also know that I mean 3am tomorrow and not say in 3 minutes from now or 3pm?

View 14 Replies View Related

General :: Any Way To Store Output Of Command Into Variable?

Mar 3, 2010

I tried using the tail command in my shell script and storing that value in a variable a but an error keeps coming. Is there any other way to store the output of a command into a variable. Cannot Read text from text file and store it in a variable using shell script. The thing is I need a number from the file new.txt and use that number in my script

#!/bin/bash
a = `tail -1 new.txt|head -n 1`
echo $a

View 2 Replies View Related

General :: Store Result Of Wc -l Command In Variable?

Apr 19, 2011

I want to store the result of wc -l as a variable so I can use it later in my script...so far unsuccessfully.

I have tried this:

set `echo awk '{ print $1, $6}' | wc -l` | echo $1

but it is far from working.

View 11 Replies View Related

Software :: How To Express Built-In Variable, RS In Awk Command

Apr 26, 2011

I am going to separate records with the string, "[J.System Info]" in awk command.

Both of the following expressions don't work well.

Code:
RS = "[J.System Info]"
(or)
RS = "[J.System Info]"

View 1 Replies View Related

Ubuntu :: Variable In A Script Error (command Not Found)?

Jan 13, 2010

I have the following script:

Code:
#!/bin/bash
for HOSTS in server01 server02 server03
do
echo "Connecting to $HOSTS"
echo "Resetting Password"
echo ""

[Code]...

done When I run the script I get an error message on the hosts that says: pass=test command not found. Any ideas why is not taking it as a variable?

View 1 Replies View Related

General :: Simple Bash Command Causing Bad Variable Name

Feb 18, 2010

When 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.

View 7 Replies View Related

General :: Does The Output Of The Previous Command Get Stored In Any Variable

Mar 26, 2011

For example, when using bash you can use

Code:

to execute the previous command or

Code:

!<number> to execute the Nth command(use history to see the list). Or you can use

Code:

cd !-2:1

to cd into the value in the first field that was executed 2 commands ago Anyhow, say I run a command and the output is a path. Any way to cd and then some variable where OUTPUT of the previous command was stored? A variable that always stores the OUTPUT of the last command.

View 8 Replies View Related

General :: Environmental Variable In Bash Command String?

Feb 9, 2011

I 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?

View 6 Replies View Related







Copyrights 2005-15 www.BigResource.com, All rights reserved