vely:get-sys

get-sys

Purpose: Obtain data that describes the system.

get-sys \
    environment <var name> | web-environment <var name> \
        | os-name | os-version \
    to [ define ] <variable>

System-describing variables can be obtained with get-sys statement and the result stored into <variable>. The following system variables can be obtained:

"environment" returns the name of a given environment variable <var name> from the Operating System, such as in the following example, the HOME variable (i.e. the path to user's home directory):
```
get-sys environment "HOME" to define home_dir
```
Generally, environmental variable needs to be set before starting the vf program manager, or set during the program execution.
"web-environment" returns the name of a given environment variable <var name> from the web server, such as in the following example, the QUERY_STRING variable (i.e. the actual query string from URL):
```
get-sys web-environment "QUERY_STRING" to define home_dir
```
Note that the same name can be used for both Operating System environment variable (the "environment" clause) and for Web Server environment variable ("web-environment" clause), hence two separate clauses for them.
"os-name" is the name of Operating System.
"os-version" is the version of Operating System.

Note that all the string values above should be treated as constants - do not change them as that may cause program to malfunction. If you want to alter any of these values, make a copy first (see copy-string).

Examples

Get the name of the Operating System

get-sys os-name to define os_name