How can I diff two files, deleting lines in file1 from file2

wavers

7/1/23, 1:31 AM

I want to take file1 and remove all the lines that are contained in file2, ideally keeping the filename file1 once done, keeping the unmodified lines of anything remaining.

I've tried using diff as follows

diff --suppress-common-lines file1 file2 > newfile

This gives me either and output < or > at the start of each line depending on the order of the two files, which I don't want.

Also tried using comm:

comm -23 file1 file2 > newfile

this requires line to be re-ordered, and the lines I have are all order sensitive.

Any idea how I can achieve this?

0 + 0

command-line

diff

text-processing

steeldriver

7/1/23, 1:58 AM

It *sounds* like you want something like `grep -vxFf file2 file1` or `awk 'NR==FNR{a[$0]; next} !($0 in a)' file2 file1` - see for example [Comparing two text files and save the missing](https://askubuntu.com/questions/1153850/comparing-two-text-files-and-save-the-missing)

frabjous

7/1/23, 3:42 AM

@steeldriver make that an answer

wavers

7/1/23, 4:43 AM

Thanks for the suggestions. This work for the most part, the files are an comparing are network switch configurations, which use the ! character between sections. Both these solutions remove these characters, and I would like to keep them. is there a way to keep those characters?

steeldriver

7/1/23, 12:10 PM

@wavers please [edit] your question with a minimal example of the 2 files and your desired output. Or delete this question and ask a more specific one - as it stands, it's a duplicate of the one I linked.

wavers

7/1/23, 1:51 PM

Never mind, my base fil included the !, took those out and all is good. Thanks

Elon Musk

I sit in a Tesla and translated this thread with Ai:

EN: How can I diff two files, deleting lines in file1 from file2

TH: ฉันจะแยกไฟล์สองไฟล์โดยลบบรรทัดในไฟล์ 1 ออกจากไฟล์ 2 ได้อย่างไร

RO: Cum pot diferenția două fișiere, ștergând linii din fișierul 1 din fișierul 2

RU: Как я могу сравнить два файла, удалив строки в файле1 из файла2

VI: Làm cách nào tôi có thể phân biệt hai tệp, xóa các dòng trong tệp1 khỏi tệp2

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