DVT IDE for VS Code SystemVerilog User Guide
Rev. 24.1.15, 10 July 2024

1.5 Set the License

In order to use DVT's features, you must obtain and set the license.

The license must be passed to the application through one of the following environment variables:




Environment variables will be read in the order above and the first non-empty value will be used, the others will be ignored. Any variable containing only the string "FLEXLM" (case-insensitive) will be ignored.

Environment variables must be set before starting the application and the application must inherit the variables (e.g. when setting the variables in a terminal the application must be started from the same terminal).

The license can also be passed through the "DVT.license.source" setting accessible by using the "Preferences: Open Settings" command. Its value has precedence over license environment variables when "DVT.environment.precedence" is set to "Settings environment variables".

The license environment variable or setting value must contain one or more FlexLM license sources. Supported license sources are:

  • File-system path of a license file: /path/to/dvt.lic

  • License server address as port@host: 27001@licsrv

  • Three-server redundancy triad with comma (,) separated license servers: 27001@licsrv1,27001@licsrv2,30001@licsrv3

  • File-system path of a directory containing one or more license files with .lic extension: /path/to/lic_dir

  • Multiline string with the content of a license file surrounded by three curly brackets: {{{...}}}

Multiple license sources, with the exception of multiline string, can be specified by separating them with:

  • colon (:) on Linux/MacOS

  • semicolon (;) on Windows

  • ampersand (&) on any OS

Notes on using IPv6 license servers:

  • If the host part of port@host is an IPv6 address, make sure to always include the ampersand (&) separator before or after, even if there are no more license sources.

  • If the host part of port@host is resolved by DNS to both IPv6 and IPv4 addresses while the server is only IPv6 accessible, the application must be started with the '-Djava.net.preferIPv6Addresses=true' vmargs.

The license features are checked out when a DVT Language Server is started by VS Code. A license indicator is available in the application's status bar, selecting it will open the license log.