franklin:/ $ su system
franklin:/ $ cd /storage/A623-C070/pvr_trp/
franklin:/storage/A623-C070/pvr_trp $ ls -la
total 57464
drwxrwx--x 2 root sdcard_rw     4096 2019-05-22 19:28 .
drwxrwx--x 6 root sdcard_rw     4096 1970-01-01 05:30 ..
-rwxrwx--x 1 root sdcard_rw  7800852 2019-05-22 19:27 20190522_192717_1558533436.trp
-rwxrwx--x 1 root sdcard_rw  5474324 2019-05-22 19:27 20190522_192745_1558533463.trp
-rwxrwx--x 1 root sdcard_rw 30148628 2019-05-22 19:26 20190522_192809_1558533488.trp
-rwxrwx--x 1 root sdcard_rw 15403028 2019-05-22 19:28 20190522_192814_1558533492.trp
franklin:/storage/A623-C070/pvr_trp $ cd /mnt/media_rw/A623-C070
/system/bin/sh: cd: /mnt/media_rw/A623-C070: Permission denied
2|franklin:/storage/A623-C070/pvr_trp $ id
uid=1000(system) gid=1000(system) groups=1000(system),1004(input),1007(log),1011(adb),1015(sdcard_rw),1028(sdcard_r),3001(net_bt_admin),3002(net_bt),3003(inet),3006(net_bw_stats),3009(readproc),3011(uhid) context=u:r:su:s0