It would depending on the specific version of Unix OS you are running and what type of patch. But if you are referring to Unix OS vendor suuplied patches, then the command would be swlist for HP-UX, for Solaris the command would be pkginfo, for AIX the command would be lslpp and for RedHat Linux the command would be rpm. If the patch you are referring to is not supplied by a Unix OS vendor the above commands for each Unix OS will work if they have distributed in the native Unix OS software distribution format. Otherwise it gets trickier and you would have to depend on the patch vendor to supply binaries that have version control strings so you can use Unix tools like what, id, ident - depending on the platform to extract the version control string to determine if a patch is installed and it might not be complete.

It would depending on the specific version of Unix OS you are running and what type of patch. But if you are referring to Unix OS vendor suuplied patches, then the command would be swlist for HP-UX, for Solaris the command would be pkginfo, for AIX the command would be lslpp and for RedHat Linux the command would be rpm. If the patch you are referring to is not supplied by a Unix OS vendor the above commands for each Unix OS will work if they have distributed in the native Unix OS software distribution format. Otherwise it gets trickier and you would have to depend on the patch vendor to supply binaries that have version control strings so you can use Unix tools like what, id, ident - depending on the platform to extract the version control string to determine if a patch is installed and it might not be complete.