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rashmi88 06-14-2017 06:09 AM

Create new file in bash using date as condition
 
I need to create a new file using bash based on the date provided in the file. The contents are provided in the notepad file like shown below. Here for every date mentioned I need to create a file and name it with that particular date.

Date: 01-01-2007
CPU 3 7098 21294
Monitor 2 6500 13000
Mouse 20 300 6000
Total: 40294
---------------------------------------
Date: 02-01-2007
CPU 3 7099 21297
Monitor 2 6501 13002
Mouse 20 301 6020
Total: 40319
---------------------------------------
As I am very new to shell scripting, not sure how to start with this request.

rtmistler 06-14-2017 06:37 AM

Hi rashmi88 and welcome to LQ.

Some suggestions are to review the following links about bash scripting and make some attempts at a first script that just runs a command or two.

As I say a lot, "Whatever you can type in the command line, you can put into a bash script."

This is because a bash script is also command line commands, running automatically.

Here are the links:
Bash for Beginners
Advanced Bash Scripting Guide
My Bash Blog

With regards to your question, you seem to have defined part of the intent or method needed to do your script. My concern is that many times people ask a seemingly simple first question, get past that, and then their real needs or requirements start showing up. Either case, it is fine to start fundamentally. You seem to be saying, "Find a date record, and create a new file using that date as part of the name", and then you have no further information about what goes into that file.

To create a file on the command line you can do something like:
Code:

$ echo abc > 123.txt
And this will create a file named 123.txt and put the string abc into it. To go one step further, you can assign a variable to contain the string, "abc", and as I'm saying above, you can even do this directly in the command line:
Code:

$ newvar=abc
$ echo $newvar
abc
$ echo $newvar > 123.txt

Just some minor tips, you really will need to experiment a bit to get the results you wish for. I also suggest you start with a small input file where you keep a backup copy so that you can repeatedly try your initial scripts until you refine them enough to get where you wish it to be working.

BW-userx 06-14-2017 09:28 AM

removed due to Mods option

wpeckham 06-14-2017 09:31 AM

Quote:

Originally Posted by BW-userx (Post 5722641)
have written down or in your head gone through the steps in what is needed to be done to get the needed results yet?

Logic board (steps)

I recommend getting it on paper, with charts, graphs, or drawings if they seem to help. Every minute you save on design saved ten in coding, and hundreds in support and modification later.

scasey 06-14-2017 11:15 AM

Quote:

Originally Posted by wpeckham (Post 5722644)
I recommend getting it on paper, with charts, graphs, or drawings if they seem to help. Every minute you save on design saved ten in coding, and hundreds in support and modification later.

This is a tad off-topic, but I think wpeckham is being too conservative about the value of design, having spent years maintaining and modifying poorly designed applications. I think it's more like 1 minute in design saves hundreds in coding and thousands in support. Just sayin'

I'm interested in seeing the response from the OP. The project appears to be a challenging, but do-able, task. As stated, we just need more information first.

BW-userx 06-14-2017 11:30 AM

removed due to Mods option

rashmi88 06-14-2017 11:41 AM

Sorry, for not being clear. User will give a filename as input argument, that file(a notepad file .txt) will contain the contents as shown below

Date: 01-01-2007
CPU 3 7098 21294
Monitor 2 6500 13000
Mouse 20 300 6000
Total: 40294
---------------------------------------
Date: 02-01-2007
CPU 3 7099 21297
Monitor 2 6501 13002
Mouse 20 301 6020
Total: 40319
---------------------------------------

Now, the script should read the contents of the file and check for the date and create a new file and name it with that date. For example, here we have 01-01-2007 as the first date available, script should read this from the file and create a new file and then copy the contents(CPU, monitor and details mentioned above) till the dashed line. For 02-01-2007, script should again create a new file and will have the contents mentioned till the dashed line. so, like this for every date, separate file needs to be created and store the contents.

I know to create a new file, i know to name it on today's date. But my question here is how to read a date from a notepad file and then create a new file on that date and then copy contents!! Thanks in advance for the help.

BW-userx 06-14-2017 11:51 AM

removed due to Mods option

schneidz 06-14-2017 12:09 PM

Quote:

Originally Posted by rashmi88 (Post 5722688)
Sorry, for not being clear. User will give a filename as input argument, that file(a notepad file .txt) will contain the contents as shown below

Date: 01-01-2007
CPU 3 7098 21294
Monitor 2 6500 13000
Mouse 20 300 6000
Total: 40294
---------------------------------------
Date: 02-01-2007
CPU 3 7099 21297
Monitor 2 6501 13002
Mouse 20 301 6020
Total: 40319
---------------------------------------

Now, the script should read the contents of the file and check for the date and create a new file and name it with that date. For example, here we have 01-01-2007 as the first date available, script should read this from the file and create a new file and then copy the contents(CPU, monitor and details mentioned above) till the dashed line. For 02-01-2007, script should again create a new file and will have the contents mentioned till the dashed line. so, like this for every date, separate file needs to be created and store the contents.

I know to create a new file, i know to name it on today's date. But my question here is how to read a date from a notepad file and then create a new file on that date and then copy contents!! Thanks in advance for the help.

sed, grep, cut, awk, paste, cat, tac, rev, tc... in that order.

BW-userx 06-14-2017 12:14 PM

removed due to Mods option

schneidz 06-14-2017 12:17 PM

^ i was just being obtuse. op should use any mixture of text manipulation programs available since linux (at least bash scripting) was designed mostly for automated text manipulation.

also, op should date things according to yyyy-mm-dd so that it sorts better.

BW-userx 06-14-2017 12:32 PM

removed due to Mods option

rtmistler 06-14-2017 05:03 PM

@BW-userx:

This thread is not for you to demonstrate or cite your coding knowledge or for you to judge the OPs needs and intentions.

The OP has been given good advice on how to script and perhaps they should start and post what they have to gain some further assistance.

BW-userx 06-14-2017 05:17 PM

Quote:

Originally Posted by rtmistler (Post 5722783)
@BW-userx:

This thread is not for you to demonstrate or cite your coding knowledge or for you to judge the OPs needs and intentions.

The OP has been given good advice on how to script and perhaps they should start and post what they have to gain some further assistance.

demonstrate or cite your (my) coding knowledge ?

then I will remove all my advice and examples on how one could "code" in order to do what the OP needs to do what he requested, and let him go and search and let him try and figured out how to do what he needs to do by learning everything that others suggested he learn by drawing from their coding knowledge and with and without citing any examples.

or for you (me) to judge the OPs needs and intentions.

you judged what he needs and his intentions are along with everyone else that said, here this is what you (OP) need in order to do what he (OP) need(s) to do. but it is not for me to do, just you and others but not me. That's interesting...

I've removed all of my advice and examples and links to try and help guild him to figuring out how to do what he needs to do in the most simplest and non time consuming manner.

Turbocapitalist 06-15-2017 12:09 AM

Quote:

Originally Posted by rashmi88 (Post 5722604)
As I am very new to shell scripting, not sure how to start with this request.

I'd say wpeckham's advice about figuring out the workflow is important. But unfortunately that workflow is somewhat dependent on the tool(s) used. Thus you have a bit of a circular dependency. To break that, I'd nudge you in the direction of awk or perl, mainly the former. I see a way to do it with two instructions with awk -- if the date field is always first in each block.

Regardless of which tools you start with, please post what you have begun so we can see the direction you are taking and can offer advice.


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