Shell Programming and Scripting

Let me try my best to give you a picture of what I'm trying to do. Once again I'm sorry for the essay thats coming up.

I programmed a rather large library of script functions to deal with input, displaying ANSI block graphics, playing sounds, and refining the terminal and so on. I also designed a file format for displaying ANSI block characters in a complete group onto the screen.

The library is completely working. Graphics display properly, I can save a graphics file, and load the image on to terminal. Sound properly plays sequences of notes, etc.

Now here is where my problem arises. I hate designing graphics files for my library. I have to manually type in each ANSI escape code to make an image, and its extremely hard to make an image. So I decided to write an application to edit the ANSI graphic file images.

The program works, I set up the interface and painting works properly. BUT! I need to find a way to save the blocks on the screen into a file. This is what I did so far: I set it so whenever you paint onto the screen, it saves the respective escape code sequence into a file. That works, but the problem is, the escape codes get saved into the file sequentially in a line, so when you load the image, its just a line of colors.

So I'm asking if theres a way to navigate through the file with commands and add text, etc. so I can implement it in my paint program?

Can I for example, use "sed" to navigate around the file and add text, etc.?

Thank you for your time.

Your question is very generic.

Please, be specific displaying a sample input and desired output.

Can I use "sed" to go to a certain column or row in a text file and delete or add text?

Yes you can used sed.

Code:

root@bt:/tmp# cat file
1
2
3

#to append/add a line after line 2
root@bt:/tmp# sed '2 a\
ahamed' file

1
2
ahamed
3

#to insert a line at line#2
root@bt:/tmp# sed '2 i\
ahamed' file

1
ahamed
2
3

#to delete line#2
root@bt:/tmp# sed '2d' file
1
3

#to change line#2 to something else
root@bt:/tmp# sed '2 c\
ahamed' file

1
ahamed
3

etc etc

--ahamed

Wow. Thanks

Can you be specific on how to move to a column, then to a row with sed?

May be you can help us with giving us more specific details of what you want.

--ahamed

For example, I want to open a text file, move to the 2nd row, 10th column in the file, and put the escape code "\n".