eu/iwb/path_os2 is a SAP Parameter attribute which is used to control Info Workbench: File path for Help on OS/2 platforms information. This is available within R/3 SAP systems depending on the version and release level.
Below is the standard documentation available and a few details of the attributes values .
The parameter specifies the path under which the Extended help is stored
for display on OS/2 front-end hosts. All languages specified with the
parameter eu/iwb/installed_languages must exist in the subdirectories of
this directory which contain the different language versions of the
help. The names of these subdirectories must consist of the two-digit
language identifier of the relevant version.
See SAP Parameter Documentation for full SAP documentation for this profile parameter.