how to solve "wodim: No such file or directory" in ubuntu 12.04?

Question

I'm executed a cd writing command in terminal it will work successfully, but if call this script from a php use exec(), it will output some errors in my log file. Is there any configuration needed in /etc/wodim.conf?

Cd writing command:

cdrecord -v -eject -multi speed=16 /tmp/newcd.iso

My log file contents

wodim: No write mode specified.
wodim: Assuming -tao mode.
wodim: Future versions of wodim may have different drive dependent defaults.
wodim: Operation not permitted. Warning: Cannot raise RLIMIT_MEMLOCK limits.
Device was not specified. Trying to find an appropriate drive...
Looking for a CD-R drive to store 27.90 MiB...
Detected CD-R drive: /dev/cdrw
Using /dev/cdrom of unknown capabilities
scsidev: '/dev/cdrom'
devname: '/dev/cdrom'
scsibus: -2 target: -2 lun: -2
scsidev: '-1'
devname: '-1'
scsibus: -2 target: -2 lun: -2
wodim: No such file or directory. 
Cannot open SCSI driver!
For possible targets try 'wodim --devices' or 'wodim -scanbus'.
For possible transport specifiers try 'wodim dev=help'.
For IDE/ATAPI devices configuration, see the file README.ATAPI.setup from
the wodim documentation.
TOC Type: 3 = CD-ROM XA mode 2

please help to solve this issue, and i'm using ubuntu 12.04 LTS

Answer 1

Please execute cd writing command using sup user power... Here sudo cdrecord -v -eject -multi speed=16 /tmp/newcd.iso