error when trying to use "strcmp" and "execname" on ubuntu 17.04

[prakashsurya]

This is my first time trying to use ply, so I apologize if this is a self induced issue, but I'm trying to execute the following command (example taken from the man page):

$ sudo ply -c 'kprobe:SyS_* / !strcmp(execname, "dd") / { @[func()].count() }'
ERR static_post         : node:<auto>.strcmp (type:call/none size:0x0 loc:nowhere) : Invalid argument
ERR annotate_script     : static type inference failed

Any clues as to what might be causing the error? and/or maybe point me to some docs/source code so I can try to read up on how this is supposed to work?

I built ply from source, and am using an Ubuntu 17.04 system:

$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description:    Ubuntu 17.04
Release:        17.04
Codename:       zesty

$ uname -a
Linux ubuntu 4.10.0-19-generic #21-Ubuntu SMP Thu Apr 6 17:04:57 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux

$ ply -v
ply-v1-beta1(9e810b1) (linux-version:264712~4.10.8)

I had to download Ubuntu's kernel sources, and use the --with-kerneldir option to workaround #7

[prakashsurya]

sorry for the noise. reading the manual some more, I see that execname should actually be execname(); the parenthesis were left out in the example I was copying, and resulted in that error message.

it's working now:

$ sudo ply -t 10 -c 'kprobe:SyS_* / !strcmp(execname(), "dd") / { @[func()].count() }'
341 probes active
de-activating probes

@:
sys_rt_sigaction               3
sys_mmap                       7
sys_write                 486862
sys_read                  487095