Calling outer program which accesses I2C device with system( ) in Linux, does not work

first at all, I list the environment below.

Calling outer program with system( ) in Linux, but outer program which access I2C device doesn’t work well?

first at all, I list the environment below.
Hardware : Raspberry Pi Zero 2w
OS:Raspberry Pi OS (Legacy) Lite
USED Interface : UART, I2C