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Replacing last line with awk and change the file name

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# 1  
Old 08-21-2014
Replacing last line with awk and change the file name
Hi Guys,

I am having a set of date format files files where I am performing the below set of operations in the files . I Need to replace the last line value with specific date which is a pipe delimited file.

for eg
Code:
f1_20140101.txt
 
aa|aus|20140101|yy
bb|nz|20140101|yy
.
.
3|20140101|zz
 
f2_20140101.txt
 
aa|aus|20140101|yy
bb|nz|20140101|yy
.
.
3|20140101|zz

I need to replace the file names f1_20140101.txt,f2_20140101.txt to f1_20140303.txt, f2_20140303.txt and to replace the last line like below
Code:
f1_20140303.txt
 
aa|aus|20140303|yy
bb|nz|20140303|yy
.
.
3|20140303|zz
 
f2_20140303.txt 
aa|aus|20140303|yy
bb|nz|20140303|yy
.
.
3|20140303|zz

the changed value columns are fixed postition
Last edited by rbatte1; 08-21-2014 at 12:15 PM..
# 2  
Old 08-21-2014
Dear rohit_shinez,

I have a few to questions pose in response first:-
  • What have you tried so far?
  • What output/errors do you get?
  • What OS and version are you using?
  • What are your preferred tools? (C, shell, perl, awk, etc.)
  • What logical process have you considered? (to help steer us to follow what you are trying to achieve)
Most importantly, What have you tried so far? There are several threads on this sort of thing already, but it depends what OS & version you are using as to whether the features exploited are available.

There are probably many ways to achieve most tasks, so giving us an idea of your style and thoughts will help us guide you to an answer most suitable to you so you can adjust it to suit your needs in future.


We're all here to learn and getting the relevant information will help us all.



Robin
# 3  
Old 08-23-2014
Hi,

I am using Sun Solaris OS and its a shell script
so far i have tried with below code
Code:
for i in f1*.txt
do
awk 'BEGIN {OFS=FS="|"}$3==20140101{$3=20140303}{print}' $i>$1temp
mv $itemp `basename "$i" temp`.20140303
done

But not able to replace the last line of my file and the file name is not getting replaced based on the below output i required
Code:
f1_20140303.txt
 
aa|aus|20140303|yy
bb|nz|20140303|yy
.
.
3|20140303|zz
 
f2_20140303.txt 
aa|aus|20140303|yy
bb|nz|20140303|yy
.
.
3|20140303|zz

Last edited by Don Cragun; 08-23-2014 at 02:55 PM.. Reason: Fix bold tags
# 4  
Old 08-23-2014
Your desired output is a little ambiguous. Are the filenames included as text on the first line in the files?

Is the number to be replaced in the files a constant, or should it be extracted from the name of the file being processed.

Your for loop is only looking for files starting with f1, but it looks like you want to process all files starting with f and ending with .txt or maybe starting with f followed by one (or one or more) digits followed by an underscore and any string of 8 digits (or a particular string of 8 digits) followed by and ending with .txt. Please describe in English which set of files should be processed.

If more than one date's input files are to be processed as a set and the output files are supposed to have a single output date, are the numbers between the f and the _ in the output filenames supposed to be adjusted? If so, does the output order matter? Will there ever be more than 9 input or output files for a given date?
# 5  
Old 08-23-2014
Apart from what Don Cragun says, two comments on your script:
- as you want to rename the files anyhow, no temp file is needed (whatever $1temp may be, and the new file name will not be what you specified in post#1).
- the last line is not modified as the date string is in field 2 there, not in field 3.
# 6  
Old 08-23-2014
Hi,

Let me be clear on the requirement

1. Files which ever starting from f and ending with .txt i.e. f*.txt. All the files naming standard will be in the format f1_YYYYMMDD.txt.
2. Need to replace the file naming standard to specific date for e.g. f1_20140101.txt to f1_20140303.txt
3.The step 2 condition will be done based on the replacing the dated column to specific date say here to 20130303. My input file i.e f1_20140101.txt will have data like this:
Code:
aa|aus|20140101|yy
bb|nz|20140101|yy
.
.
3|20140101|zz

the input file will follow the same pattern i need to replace the
1. 3rd dated position column to 20140303 in rest of lines
2. 2nd dated position column to 20140303 in last line of the input file

output some thing like this with file name replaced to f1_20140303.txt
Code:
aa|aus|20140303|yy
bb|nz|20140303|yy
.
.
3|20140303|zz

# 7  
Old 08-23-2014
You might want to try this straightforward solution, which would satisfy your requirements with your sample data, but might fail with other file structures that you did not mention yet:
Code:
OD="20140101"; ND="20140303"
awk -v OD="$OD" -v ND="$ND" '{sub (OD, ND, FILENAME); sub (OD, ND); print > FILENAME}' f*.txt

ls -1 f*.txt
f1_20140101.txt
f1_20140303.txt
f2_20140101.txt
f2_20140303.txt

cat f1_20140303.txt 
aa|aus|20140303|yy
bb|nz|20140303|yy
.
.
3|20140303|zz

This User Gave Thanks to RudiC For This Post:
rohit_shinez
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