Programming :: Updating A Single Line In A Text File?
Dec 30, 2010
I have a text file called namelist.wps. In this file there is a line that reads:Code: start_date = '2010-12-26_12:00:00', '2010-12-26_12:00:00', I have to automatically update the year, month, and day of month. I set values for the year, month, and day of month using the following code in a c-shell script:Code: set y1 = `date +%Y`set m1 = `date +%m`set d1 = `date +%d` After I do this, how do I update year, month, and day of month, without changing any of the other lines in the namelist.wps file?
I have a text file called namelist.wps. In this file there is a line that reads:
Code: start_date = '2010-12-26_12:00:00', '2010-12-26_12:00:00', I have to automatically update the year, month, and day of month for this line without changing the rest of the file. Here is the script that I have:
I have to delete a certain line of text from the a textfile via ubuntu's shell scripting.I have done research, and it seems that most people advocate the usage of sed /d option. sed makes does not edit the text file. Hence, most options I discovered involved the use of a temporary variable/textfile and then overwriting the old file with the temporary new file. Is there anyway whereby I can bypass the use of temporary storage containers? I hope there is any magical combination of commands to edit the file directly.
I have two txt files containing x and y coordinates: xcoord.txt & ycoord.txt. I need to open them; read them line by line to get each coordinate; then each time I need to update Xs and Ys parameters inside another file called "dc.in" with the grabbed values.
Finally each time I need to run two exe files ( dc_2002 and st_vac) and produce corresponding output for each Xs and Ys ( dc.in is an input file for this exe files)
I have written the following code but it does not work:
Was wondering if any perl guru's could help me with a quick log file adjustment. I have a text file that looks like so (tabs and newlines are revealed so you can see what separates the data):
There are maybe 100 lines of text in this file at any given time. I need to delete all duplicate lines only looking at the first bit of text prior to the first tab. It doesn't matter which one gets deleted as long as there are no two lines that begin with that same text at the beginning before the first tab. So in this example, either the fist line "1234" or the last line "1234" would need to be deleted. I already have code in my script that opens the files - I just need the code to read the text into an array and the part that would find matches based on the above criteria, and make the deletions.
If it would be easier, I can even do a system call and use SED (v4.1.5) and/or AWK (3.1.5) instead.
bash 3.1.17(2) I'm trying do write a shell script which must operate on each line of an ASCII text file. So, all the code must be inside a loop, and inside the loop, the first thing should be to read the next line from the file. I have the bash read command. But it reads from stdin. Any way to make read from a file?
a sed command to add a text before line number in text file? I have text file with 500 lines, and i want to add 3 more lines with text after line 300, OR before line 302, isn't no problem.
Say I have a text file like: Code: 1 3 4 How would I use ksh to put the number '2' into the second line of that file?Okay it's not bash, it's ksh because this computer is OpenBSD
I am thinking of appending something to each line in a text file with Java. I prefer not write a new file with content appended from the old one.That 'something' would probably be Time Stamp when the file is created (which is same for each line).I am not sure Java provide some easy way for it or not
im trying to output a list of running processes via a shell script. At the moment i got this which outputs the processes to a text file called out.
echo $(ps aux) >>out
The problem is though, the processes are all just one big block of text which makes it hard to read. Does anyone know how to sort the output to a text file so that it prints to the text file at 1 process per line? I know its probably simple but im very new to linux.
I'm a bit new to Python programming and hoped that someone might be able to help with a problem I'm having. What I essentially want to do is to combine two text files line for line. I know how to do this in a bash script so to give you a better idea here's the code for that:
Code:
This is basically for adding on values to the end of a CSV file that uses ';' as the delimiter. So say file1 said:
And file2 said:
Then running this command would create merged_file1_and_file2 which would be:
The code I'm using at the moment is:
Code:
As I'm sure any experienced python programmer will see, this prints out the first line of the file "csvraw" and then all of the lines of "stamps" and then the remainder of "csvraw".
What I'd like to do is something like: (pseudo code, I know it's not python ;-))
Code:
Is this possible? I've tried googling and my Python Pocket Reference hasn't been much help. I've looked at pickling but that doesn't seem appropriate.
I want to search a file for a particular pattern and if pattern found replace the line with new text. i am using awk 'match($0,"pattern") != 0 {print $0} ' filename to check if the pattern exists.how do i get the line number of the pattern and delete that line and replace the line with my new text?
Running Ubuntu and writing simple C programs. I need 2 text windows, the one I have started in, and a second to display some debug information. I can start a second screen using popen("/usr/X11R6/bin/xterm" "w"), and I get my new text window. However, it is running a shell and I can't send any info to it!
I'm trying to add text to a file for a specific group of users, I'll need to do examples as I can't think of an easy way of explaining, my file is like this:
Code:
users{ user1 user2
[code]....
At the present my code lists all the available groups, how would I add a user to a specified group? (e.g add "members user3") to the end of group 1 for example. So the code ends up like this
AKA "zipping on the fly .. the slow-as-molasses way." The list includes full pathnames to each file, and they're all in subfolders of the same parent folder (which, unfortunately, is not the root folder of the drive or system on which the files reside). A cleaned-up and radio-ready portion of the list looks like
What I'd like to be able to do is zip all the files in the list into a single archive, to avoid the step of having to copy them to the same location (presumably another folder on the HD) and then zip that folder. I'm more inclined to make provisions about extracting to a single folder at some other time. Is this possible in BASH, or would I have to consider a faster, more robust scripting language such as python or perl?
I want to access a file, and check the length of every line.After, i want to check and replace all lines with length over 10 characters, with a message.Does anyone have a clue on that?
I need to be able to convert HTML email messages saved as text files (.eml or .msg) to PDF documents, one PDF per email, retaining formatting and images.
Are there any Linux tools that will allow me to do this from the command line (so it can be scripted)?
I need to insert 3-4 lines of text to the beginning of a text file. The file is a largish MYSQL dump, the result of a backup shell script. This shell script should insert the required text.I've wrestled with sed, but lost.
I want to display something in my text view widget in glade using c code. that's all right. now I need to attach a save button beneath the text view.so that on click the text view content should save as a txt file..
I want to display the contents of a particular log file (simple text file, I mean in Linux). But there is a problem: The contents need to be organized in a fixed format. Have a look at this log file:
So, while displaying the contents of above file on a web page, I want to format the field names found in the log file: User Name:, Reported Problems Description:, and Remarks:. These fields may contain a variable length of text and no specific line number is assumed for them to appear on.
Well, what I am trying to do may sound wierd to some of you. The filed "Reported Problems Description:" can possible contain text which embeds colon (.
I want to get the last term of an unknown-sized text line, by usig the awk command. Is there any variable which points to the last term of a text line ? (obviously, y can obtain that term if i knew how many terms does the line have... i.e. awk '{print $12}' ; if we are talking about a 12-terms text line) I wonder if there is an option like $?, to get the last term.
I would like to insert prior to the word "three" all items from this second file with the following contents:
Code:
four three two one
Now my issue is, and I have been using both sed and awk currently, that after the second line of the new file is read there will of course now be 2 copies of the word "three" but I would like to only insert the final 2 words, ie "two" and "one" prior to only the first occurrence of the word "three" so final file will look like:
Code:
one two four
[code]....
So here there is now only one of each word from the second file joined to make the new file. For simple code I have tried something like the following:
Code:
while read line do awk -v n=$line '!f && /three/{print n;f++}1' file1 > tmp_file mv tmp_file file1 done < file2
Now this works but seems very clumsy to me. There is obviously a better sed and / or awk out there.
