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Add to the end of a line containing a pattern - with sed or awk

Here is example file

somestuff...
all: thing otherthing
some other stuff

What I want to do is to add to the line that starts with all: like this:

somestuff...
all: thing otherthing anotherthing
some other stuff

I probably can do this using sed, but I am not really good in sed, so could anyone help with it?

print second last column/field in AWK

I want to print the second last column or field in awk. The number of fields is variable. I know that I should be able to use $NF but not sure how it can be used.

And this does not seem to work:

awk ' { print ( $NF-- )  } '

split string to array using awk

How to split the string when it contains pipe symbols | in it. I want to split them to be in array.

I tried

echo "12:23:11" | awk '{split($0,a,":"); print a[3] a[2] a[1]}'

Which works fine. If my string is like "12|23|11" then how do I split them into array?

Merge two lines into one

I have a text file with the following format. The first line is the "KEY" and the second line is the "VALUE".

KEY 4048:1736 string
3
KEY 0:1772 string
1
KEY 4192:1349 string
1
KEY 7329:2407 string
2
KEY 0:1774 string
1

I need the value in the same line as of the key. So the output should look like this...

KEY 4048:1736 string 3
KEY 0:1772 string 1
KEY 4192:1349 string 1
KEY 7329:2407 string 2
KEY 0:1774 string 1

It will be better if I could use some delimiter like $ or , KEY 4048:1736 string , 3

How do I merge two lines into one?

Is there a Unix utility to prepend timestamps to lines of text?

I ended up writing a quick little script for this in Python, but I was wondering if there was a utility you could feed text into which would prepend each line with some text -- in my specific case, a timestamp. Ideally, the use would be something like:

$ cat somefile.txt | prepend-timestamp

(Before you answer sed, I tried this:

$ cat somefile.txt | sed "s/^/`date`/"

but that only evaluates the date command once when sed is executed, so the same timestamp is incorrectly prepended to each line.)

How to print last two columns using awk

All I want is the last two columns printed. thanks I am surprised this question wasn't yet asked.

Using awk to remove the Byte-order mark

has anyone an idea how an awk script (presumably a one-liner) for removing a BOM would look like?

Specification:

• print every line after the first (NR > 1)
• for the first line: If it starts with #FE #FF or #FF #FE, remove those and print the rest

Is there still any reason to learn AWK?

I am constantly learning new tools, even old fashioned ones, because I like to use the right solution for the problem.

Nevertheless, I wonder if there is still any reason to learn some of them. awk for example is interesting to me, but for simple text processing, I can use grep, cut, sed, etc. while for complex ones, I'll go for Python.

Now I don't mean that's it's not a powerful and handy tool. But since it takes time and energy to learn a new tool, is it worth it ?

find difference between two text files with one item per line

I have two files:

file 1

dsf
sdfsd
dsfsdf

file 2

ljljlj 
lkklk 
dsf
sdfsd
dsfsdf

I want to display what is in file 2 but not in file 1, so file 3 should look like

ljljlj 
lkklk 

What are the differences between Perl, Python, AWK and sed? [closed]

just want to know what are the main differences among them? and the power of each language (where it's better to use it).

Edit: it's not "vs." like topic, just information.

awk: access captured group from line pattern

If I have an awk command

pattern { ... }

and pattern uses a capturing group, how can I access the string so captured in the block?

How can I delete a newline if it is the last character in a file?

I have some files that I'd like to delete the last newline if it is the last character in a file. 'od -c' shows me that the command I run does write the file with a trailing new line:

0013600   n   t  >  \n

I've tried a few tricks with sed but the best I could think of isn't doing the trick:

sed -e '$s/\(.*\)\n$/\1/' abc

Any ideas how to do this?

What is the difference between sed and awk? [closed]

• What is the difference between awk and sed ?
• What kind of application are best use cases for sed and awk tools ?

Parsing json with UNIX tools

I'm trying to parse json returned from a curl request, like sp:

curl 'http://twitter.com/users/username.json' | sed -e 's/[{}]/''/g' | awk -v k="text" '{n=split($0,a,","); for (i=1; i<=n; i++) print a[i]}'

I have it set working where it splits the json into fields, i.e. the above returns

% ...
"geo_enabled":false
"friends_count":245
"profile_text_color":"000000"
"status":"in_reply_to_screen_name":null
"source":"web"
"truncated":false
"text":"My status"
"favorited":false
% ...

But what I would like to do is grab a specific field (denoted by the -v k=text) and only print that.

Any ideas?

awk without printing newline

I want the variable sum/NR to be printed side-by-side in each iteration. How do we avoid awk from printing newline in each iteration ? In my code a newline is printed by default in each iteration

for file in cg_c ep_c is_c tau xhpl
printf "\n $file" >> to-plot.xls
    for f in 2.54 1.60 800 
        awk '{sum+=$3}; END  {print  sum/NR}' ${file}_${f}_v1.xls >> to-plot-p.xls
    done
done

I want the output to appear like this

cg_c ans1  ans2  ans3  
ep_c ans1  ans2  ans3 
is_c ans1  ans2  ans3
tau  ans1  ans2  ans3 
xhpl ans1  ans2  ans3

my current out put is like this

**cg_c**
ans1
ans2
ans3
**ep_c**
ans1
ans2
ans3
**is_c**
ans1
ans2
ans3
**tau**
ans1
ans2
ans3
**xhpl**
ans1
ans2
ans3