General :: Assign A Variable To The Output Value Of A Program?
Feb 6, 2011so i wrote myself a very simple hellworld program in c++
...the usual stuff
int main()
{
[code]...
ADVERTISEMENT
General :: Assign Local Variable Values To Global Variable?
Feb 17, 2011how to assign a local variable value to a global variable....
View 2 Replies View RelatedProgramming :: Search Within A Variable And Assign The Results To A New Variable?
Apr 25, 2011how 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 ${cars} | egrep -o '<A?+|<C+'`
with the echo command I get the following output assigned to list -
A
C
C
What I'd like to get for output is -
Audi
Cadillac
Chevy
how I could do this regardless of upper/lower case letters?
Programming :: Assign Value Of C Variable To Shell Variable?
Apr 28, 2010included shell script inside c program, and i wanted to assign the value of c variable to shell variable..Can any one please suggest me how to do it?
View 8 Replies View RelatedGeneral :: Assign An "here Documents" Section To A Variable In Bash?
Mar 11, 2011Is it possible to assign an "here documents" section to a variable in bash?I would like to assign the following to a variable:
Code:
<html>
<body>
<p>THis is a test</p>
</body>
</html>
Red Hat / Fedora :: Assign A Variable To A Command?
Sep 10, 2010I can print a specific line of a file with:$ 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 RelatedGeneral :: Sed: Assigning Its Output To A Variable?
Feb 3, 2011Kernel 2.6.21.5, GNU/Linux (Slackware 12.0).In this script,
Code:
semoi@darkstar:~$ cat rename4.sh
#!/bin/bash
INPUT="k3b_audio_0_04"
[code]...
General :: Any Way To Store Output Of Command Into Variable?
Mar 3, 2010I 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 $a
General :: Need To Store Output Of Bitset() In A Variable / Possible In C++?
Mar 5, 2010I need to store the output of bitset() in a variable ... is it possible in c++?
View 1 Replies View RelatedGeneral :: Can't Save Grep Output Into Variable / Solution For This?
Feb 3, 2010I would like to grep two numbers out of a text file, and divide them.
Here is the script code...
It feels like grep saves a new line too? or what is happening? i simply can't divide them, as it handles the variables as they are empty (and prints the two numbers although they were not printed
General :: Does The Output Of The Previous Command Get Stored In Any Variable
Mar 26, 2011For example, when using bash you can use
Code:
to execute the previous command or
Code:
!<number> to execute the Nth command(use history to see the list). Or you can use
Code:
cd !-2:1
to cd into the value in the first field that was executed 2 commands ago Anyhow, say I run a command and the output is a path. Any way to cd and then some variable where OUTPUT of the previous command was stored? A variable that always stores the OUTPUT of the last command.
General :: Storing A Variable In A Shell Script After Awk Output?
Feb 8, 2010On command line I have no problem storing a variable e.g
Code:
:~/bin$ process=`ps -ef | awk ' $8 == "idesk" { print $2 }'`
:~/bin$ echo $process
26736
:~/bin$
When I try to incorporate this into a shell script I get a blank.
Code:
:~/bin$ cat process_idesk
#!/bin/bash
process=`ps -ef | awk ' $8 == "idesk" { print $2 }'`
[code]....
The process_idesk script has been chmoded to be executable by the user. I'm sure there must be a silly omission on my behalf.
Debian Programming :: Assign Variable In Bash When Stdout Is Updated
Jan 17, 2014I am writing a script that calls a program which writes a lot of lines to stdout continuosly. If the last line in stdout has some regex, THEN, certain variables are updated. My problem is that I don't know how to do that.
A simplified example would be (it's not my exact case, but it I write it here to clarify): suppose I issue a ping command (which writes output to stdout continuously). Every time that the response time is t=0.025 ms, THEN, VARIABLE1=(column1 of that line) and VARIABLE2=(column2 of that line).
I think the following code would work in awk (however, I want the variables in bash and I don't know how to export them)
Code: Select allping localhost |awk '{ if ( $8 == "time=0.025" ) var1=$1 var2=$2}'
In the previous code, awk analyzes each line of the output of the ping command as soon as it is created, so the variables $var1, $var2, ... are updated at the appropriate time. But I need the "real-time" updated values of $var1, $var2 in bash, for later use in the script.
Programming :: Bash Scripting...read A Value From A File Then Assign To Variable?
Feb 27, 2011At my wit's end I can't find anything that I understand well enough to use. This is for a Unix class, we are working with shell scripting. File1 has 5 in it and File2 has 100 in it.The teacher wants us to read the values then do the math. This is what I have so far:#!/bin/bashvar1='cat File1'var2='cat File2'var3=`echo "scale=4; $var1 / $var2" | bc`echo The final result is: $var3
View 9 Replies View RelatedProgramming :: Bash Script: Assign Command Ouput To A Variable Without Executing It?
Feb 12, 2011I'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]...
General :: Count The Number Of Lines Inside A File And Put The Output Into A Variable?
Feb 1, 2011i need to count the number of files and put the output into a variable. i used wc -l filename but i couldnt find an option to put the output to variable. example if the number o line is 5, i need the output of echo $x is 5.
View 3 Replies View RelatedGeneral :: Create A Single Line Of Output From Multiple Variable Lines Of Input
Feb 3, 2010I need to create a single line of output from multiple and variable lines of input in a Linux bash shell script.
My input file looks like this:
Where there may be any number of umsecondaryphonenumber lines; if there is not a umsecondaryphonenumber line for a telephonenumber, I don't want to write any output.
So, the output file should look like:
The script I have so far is:
My question is - how do print each of the elements of an array in one record - i.e. what do I put in place of howdoiprintarray?
Ubuntu :: Possible To 'assign' Program To Core?
Jul 26, 2010Obviously I don't know that much about CPU architecture. I have a fancy new quad core CPU in the machine I just built. Now, given the current state of technology, two or many times three of those cores are pretty much sitting idle.My question is: Is there any way to utilize those extra cores with programs not optimized to take advantage of them? If I have some CPU intensive application, is there any way to tell it to utilize a core that's idling instead of the first core that's probably already got a bunch of processes running on it?
View 7 Replies View RelatedGeneral :: Unexpected Output From Program?
Sep 8, 2010while doing socket/network programming, i am getting SSH-2.0-openssh4.7 error, instead of showing day time of server.general description i have Linux Box, with the help of putty i am connecting from windows system to Linux box,no problem in loging,after typing program, i am running the program with gcc. when typing ./a.out, it is showing SSH-2.0-openssh4.7, actually it should display daytime from linux box in both tcp and udp.
View 1 Replies View RelatedGeneral :: Program To Visualize Anything That Goes Through My Audio-output?
Jun 1, 2011I'm looking for a program that will visualize anything that goes through my audio-output (in this case it's Spotify) and display it on the screen. Does this exist?
I'm running Ubuntu.
General :: Assigning "find" Operation Output To A Variable?
Jan 7, 2011I am assigning "find" operation output to a variable. I also need to have error info / stderr if nothing is found in the same variable itself.
e.g.
a=`find . -name "hello.txt" -type f`
I do not want any temp files to be in between infact, redirection.
General :: Executing PHP File And Read Output To Program
Jun 29, 2011I'm using Ubuntu and I'm programing with eclipse CDT. My goal is to execute a php file and read the output to my c++ program. To do so I thought I should use fork(), dup2() and execl. When in shell, the call "php myscript.php" worked just fine, but when in c++ I tried:
execl("usr/bin/php", "php", "home/geiger/workspace/SemiServer/server_content/myscript.php", NULL);
And it didn't work (the process wasn't terminated and I got no output). I tried different version of this call, like losing the "php" string and/or drop "home/geiger" from the path string, to no better result.
General :: Redirection - Redirect The Output Of A Program To The Diff Command?
Jan 13, 2011I have a program that writes to stdout. Is there a way that I can redirect the output to the linux diff command or do I have to write the output to a file and then compare that. For example I have a bunch of test input files for a program and the corresponding expected output in another set of files. And I'd like to do something like ./program < t1.input | diff t1.expected.
View 3 Replies View RelatedProgramming :: Piping Cat Output To Variable?
Jan 10, 2010New to ubuntu and shell scripting in general... currently I stored some data into a text file. Right now, I would like to output the data from the text file and store it into a variable. Here's what I have so far:
READ_FILE=$(cat $FILE_NAME)
This definitely works and READ_FILE has the necessary data. However, this command will trigger an output to std output and I will see data on the screen, which is not what I want. I tried:
cat $FILE_NAME | $READ_FILE
and various other variants of this. It does not output to std output but neither does anything gets stored into $READ_FILE. I tried:
cat $FILE_NAME >> $READ_FILE
and it arrived at an error of "ambiguous redirect".
Ubuntu :: C++ - Can't Pass System Output To Variable ?
Sep 8, 2010I have a line that looks something like this:
Code:
How do i put its output in a variable?
Programming :: Retain The Eol In Bash Variable Or Ssh Output?
Jan 17, 2011I have to save the result of ssh/grep into a file to keep the eol ("/n"):
ssh $SSH_OPTIONS $USER@$NODE "cd $LOG_DIR; grep -h '$pattern' log.*" > $file
So that when I grep on the local file again later, it can be printed out with original log lines. Otherwise, the log lines will be dropped and lines becomes concatenated into a single line, e.g., if I rewrite the script in this way, echoing the $result is not a good idea..
result=`ssh $SSH_OPTIONS $USER@$NODES "cd $LOG_DIR; grep -h '$pattern' log.*"`
is there some workaround that I can save it to a variable rather than file but still keep the eol? That will simplify my script and don't need to do all those I/Os!
Programming :: Java Output Into Bash Variable?
Feb 20, 2011I have a bash script that calls a java class method. The method returns a string to the linux console when run independently. how can I assign the value from the java method to a variable in a bash script?running the script: java -cp /opt/my_dir/class.method [parameter]
output: my_string if added in a bash script:
read parameter
java -cp /opt/my_dir/class.method [parameter] | read the_output
echo $the_output
the above doesnt work, I also tried unsuccessfully:
the_output=java -cp /opt/my_dir/class.method [parameter]
the_output=`java -cp /opt/my_dir/class.method [parameter]`
java -cp /opt/my_dir/class.method [parameter] 2>&1
How can i get the output stored into the_output variable?
General :: Program That Reads Multiple Pipes / File Descriptors And Writes To Standard Output
Feb 23, 2011Is there already a program that reads multiple pipes or file descriptors and writes to the standard output (not splitting lines).Like cat, but reading all files simultaneously and preserving lines.It is needed to avoid coding of select/epoll loops or using multithreading in simple programs. Like "select loop for bash".
View 1 Replies View RelatedUbuntu :: Cannot Pipe Gdialog Output To Variable / Sort It?
Mar 20, 2010I'm trying to use the output from gdialog's input box in another command with no success. code...
View 3 Replies View RelatedProgramming :: Receive Command Output And Store It To A Variable?
Apr 3, 2010Suppose 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?