How Do I delete/Clean Syslog?

[minesheep]

Thanks for replying but maybe you missed it
syslog is 42GB in size.
There is not enough room on the drive to make a copy.

That is not normal. You should open it in some way. There are many ways out here just be creative

1. Make normal copy of it after purging, (few mb - few 100 mb) however this may not be safe because if you someway fail the purging You can't restore the file that you emptied
   
2. If you are advanced enough use tools that do not require the file to be copied to RAM for example hex editor
   
3. just make partitial copy of larger file "dd if=/var/log/syslog of=/home/yourusername/partitialsyslog bs=1M count=512" change count=x to get more or less megabytes and home/yourusername/partitialsyslog to change name and path.
   

Note that using commands and programs that you run without sudo only allows reading of logs not modifying them in  any way, so this is safer (to leave sudo out)than using it when it's not necessary. Of course when you need it use it but read-only mode is safer for copying and accessing without the risk of damage.