Shell Programming and Scripting

Hi,
I have 3 files with one column value as shown
File: a.txt
------------
Data_a1
Data_a2
File2: b.txt
------------
Data_b1
Data_b2
Data_b3
Data_b4

File3: c.txt
------------
Data_c1
Data_c2
Data_c3
Data_c4
Data_c5
Data_c6
Requirement is to merge all 3 columns delimitted by ":" into a new file called output.txt
Output File: output.txt
-----------------------
Data_a1ata_b1ata_c1
Data_a2ata_b2ata_c2
ata_b3ata_c3
ata_b4ata_c4
:ata_c5
:ata_c6
Similarly, I may have 4 files as input and need to combine them into new file.
File: a.txt
-----------
Data_a1
Data_a2
File2: b.txt
------------
Data_b1
Data_b2
Data_b3
File3: c.txt
------------
Data_c1
Data_c2
Data_c3
Data_c4
File4: d.txt
------------
Data_d1
Data_d2
Data_d3
Data_d4
Data_d5

Output File: output.txt
------------------------
Data_a1ata_b1ata_c1ata_d1
Data_a2ata_b2ata_c2ata_d2
ata_b3ata_c3ata_d3
:ata_c4ata_d4
:::ata_d5

Thanks in advance for your help.
Thanks,
Venkat

---------- Post updated at 11:01 PM ---------- Previous update was at 10:59 PM ----------

I am submitting again because of smile icon came for colon D characters...hence changed the data....

Hi,
I have 3 files with one column value as shown
File: a.txt
------------
Information_a1
Information_a2
File2: b.txt
------------
Information_b1
Information_b2
Information_b3
Information_b4

File3: c.txt
------------
Information_c1
Information_c2
Information_c3
Information_c4
Information_c5
Information_c6
Requirement is to merge all 3 columns delimitted by ":" into a new file called output.txt
Output File: output.txt
-----------------------
Information_a1:Information_b1:Information_c1
Information_a2:Information_b2:Information_c2
:Information_b3:Information_c3
:Information_b4:Information_c4
::Information_c5
::Information_c6
Similarly, I may have 4 files as input and need to combine them into new file.
File: a.txt
-----------
Information_a1
Information_a2
File2: b.txt
------------
Information_b1
Information_b2
Information_b3
File3: c.txt
------------
Information_c1
Information_c2
Information_c3
Information_c4
File4: d.txt
------------
Information_d1
Information_d2
Information_d3
Information_d4
Information_d5

Output File: output.txt
------------------------
Information_a1:Information_b1:Information_c1:Information_d1
Information_a2:Information_b2:Information_c2:Information_d2
:Information_b3:Information_c3:Information_d3
::Information_c4:Information_d4
::::Information_d5

Thanks in advance for your help.
Thanks,
Venkat

Try paste command

I tried Paste but it is not giving the result as expected...

Output File: output.txt
-----------------------
Information_a1:Information_b1:Information_c1
Information_a2:Information_b2:Information_c2
:Information_b3:Information_c3
:Information_b4:Information_c4
::Information_c5
::Information_c6

But Paste is giving:

Output File: output.txt
-----------------------
Information_a1:Information_b1:Information_c1
Information_a2:Information_b2:Information_c2
Information_b3:Information_c3
Information_b4:Information_c4
Information_c5
Information_c6

Code:

paste -d':' f1 f2 f3 | awk -F: -v No_of_input_files=3 ' { print substr("::",1,No_of_input_files-NF) $0 } '
Information_a1:Information_b1:Information_c1
Information_a2:Information_b2:Information_c2
:Information_b3:Information_c3
:Information_b4:Information_c4
::Information_c5
::Information_c6

Thanks alot for the code you provided.
This code worked fine.

Thanks again for your help.

Venkat

Similarly you can use 'join' command

Thanks Sanjeev for responding.
Paste worked, hence did not even try join command.
This is just for learning purpose, can you please share the code with "join". I tried but was not getting the desired result.

Thanks,
Venkat