My unix system got rebooted while editing a file. I am not finding that file after the reboot.

Look in /usr/preserver or /var/preserve. Try running the command: ex -r It should print out a list of files that were in the process of being edited when some event caused a terminal disconnect. On a system we have here, I ran the command and got: On Sat Feb 12 at 16:20 saved 125 lines of file /tmp/hdisk_iostat.sh On Sat May 15 at 11:29 saved 564 lines of file filesystems On Mon Mar 21 at 09:15 saved 5 lines of file find_full_perms.sh On Tue Oct 19 at 15:44 saved 19 lines of file get_info If I want to recover one of these files such as find_full_perms.sh, I simply type: ex -r find_full_perms.sh Since you are in an editor, simple type: :wq! and your file should be magically saved.