Technically speaking, there's only one probe being attached (from bpftrace point of view) with the list of functions passed via link_opts. OTOH, I see that this may be confusing.

At the moment, we print the amount of attached functions, along with the complete list of functions, when -v is used:

# bpftrace -v -e 'kprobe:s* { @[func] = count(); }'
node count: 7
Attaching 1 probe...
[...]
Attaching kprobe:s*
Attaching to 7867 functions
 s25fs256t_late_init
 s25fs256t_post_bfpt_fixup
 [...]

I'd suggest we change the behaviour to report

Attaching 1 probe to 7876 functions...

for the non-verbose output and add the list of functions for the verbose output.

I'm currently working on refactoring the verbosity/debug outputs so I can add this, too.

I think it's important here not to introduce anything that could be confusing to an end user as it's confusing enough as it is for them. IMO there should be no difference in the output given to a user whether they specified the probes manually or whether they obtained the list of probes to enable via globbing. Exposing the details of a 1:N mapping that kprobe multi gives could be very confusing, especially if the output is different to the non-globbed way of specifying the probes.

That's a fair point. We probably shouldn't print a different number for the same bpftrace script depending on whether the kprobe multi is used or not.