Get sys

18.4.0 released Sep 25, 2023

Get sys

Purpose: Obtain data that describes the system.

get-sys \
    environment <var name> | web-environment <var name> \
        directory | 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.
"directory" is the execution directory of the command-line program, i.e. the current working directory when the program was executed. Note that Vely will change the current working directory immediately afterwards to the application home directory (see how-vely-works). You can use this clause to work with files in the directory where the program was started. If your program runs as an application server (see FastCGI), then "directory" clause always returns application home directory, regardless of which directory vf program manager started your application.
"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