I'm trying to check if a multi-line string exists in a file using common bash commands (grep, awk, ...).

I want to have a file with a few lines, plain lines, not patterns, that should exists in another file and create a command (sequence) that checks if it does. If `grep` could accept arbitrary multiline patterns, I'd do it with something similar to

```
grep "`cat contentfile`" targetfile

```

As with grep I'd like to be able to check the exit code from the command. I'm not really interested in the output. Actually no output would be preferred since then I don't have to pipe to `/dev/null`.

I've searched for hints, but can't come up with a search that gives any good hits. There's [How can I search for a multiline pattern in a file?](https://stackoverflow.com/q/152708/204658), but that is about pattern matching.

I've found `pcre2grep`, but need to use "standard" \*nix tools.

Example:

contentfile:

```
line 3
line 4
line 5

```

targetfile:

```
line 1
line 2
line 3
line 4
line 5
line 6

```

This should match and return 0 since the sequence of lines in the content file is found (in the exact same order) in the target file.

EDIT: Sorry for not being clear about the "pattern" vs. "string" comparison and the "output" vs. "exit code" in the previous versions of this question.