lsof is a package that you have to add .you can download the file from internet as per your server .
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Place it in any directory (e.g. /root/software/lsof)
3. Go to that directory. Run the gunzip command (gunzip lsof-4.77-sol10-x86-local.gz)
4. Do a pkgadd (pkgadd -d lsof-4.77-sol10-x86-local)
5. It will show you something like the following :
root # pkgadd -d lsof-4.77-sol10-x86-local
The following packages are available: 1 SMClsof lsof (x86) 4.77
Select package(s) you wish to process (or 'all' to process all packages). (default: all) [?,??,q]:
Press enter (for default value all)
6. If in later stage it asks you whether or not to install some of the conflicting files, you may select yes.
7. The lsof utility is now ready to use.
8. Test it by running the command lsof