[inputs.exec]: Error in plugin: metric parse error

[beyondht2003]

Relevant telegraf.conf:

System info:

Steps to reproduce:

1. ...
   [[inputs.exec]]
   commands = [
   "/data/telegraf/test.sh"
   ]

test.sh file

#!/bin/sh
ias_pid=16781
heap=/nemo/jdk8/bin/jstat -gc $ias_pid|tail -n1
ias_m=echo "$heap"|awk -F " " '{print $9}'
tempv=echo "scale=0; $ias_m/1"|bc
#tempv=64100.1
echo "multi_proc,tag=tagvalue ias_m=$tempv"

2. ...
   run test.sh directly
   [app@centos telegraf]$ ./test.sh
   multi_proc,tag=tagvalue ias_m=64896

but telegraf.log does not work, cannot read the value

[app@centos telegraf]$ tail -f /var/log/telegraf/telegraf.log
2019-07-12T06:42:08Z E! [inputs.exec]: Error in plugin: metric parse error: expected field at 1:31: "multi_proc,tag=tagvalue ias_m="

[app@centos telegraf]$ sudo -u telegraf ./test.sh
Could not attach to 16781
(standard_in) 1: syntax error
multi_proc,tag=tagvalue ias_m=
user telegraf doesnot support jstat?

Expected behavior:

Actual behavior:

[inputs.exec]: Error in plugin: metric parse error

Additional info:

[beyondht2003]

#2215
Similar problem, I add telegraf to sudo and it works !