4.7 Environment Variables

To define an environment variable you can use the following syntax:

+dvt_setenv+<NAME>[=VALUE]

Examples:

+dvt_setenv+UVM_HOME=/uvm/uvm-1.1

+dvt_setenv+SPECMAN_PATH=$SPECMAN_PATH:/path/to/my/vips

To use the value of an environment variable called ENV_VAR you can use any of the following notations:

UNIX: $ENV_VAR or ${ENV_VAR}
Windows: %ENV_VAR%
Makefile: $(ENV_VAR)
TCL: $::env(ENV_VAR) or $env(ENV_VAR)

Environment variables, either from the parent shell or explicitly defined, can be used to specify:

top files
directives that take a path as an argument, for example +incdir+
value for defines

When an environment variable is not defined, but it is used, the behavior is as follows:

for the value of a define directive, the define value is left as-is
for top files and directives that take a path as an argument, an error is signaled and such top files and directives are ignored
when used inside the value of an environment variable, it is expanded to the empty string

Environment variables are visible to the DVT parsers, for example when used in the e language import statements.

Environment variables are propagated to the external tools launched from DVT, for example by using Run Configurations or External Builders.

When an environment variable is used inside a build file, only the +dvt_setenv+ directives above the usage line are taken into account.

Implementation note

The Dot '.' segment in a path denotes the current directory, which is solved when the path is used, for example to specify a top file or incdir. It is not solved when defining an environment variable. See the example below:

-------- In default.build --------
+dvt_setenv+MYVAR=. // $MYVAR has the value '.' until used to specify a path
$MYVAR/top1.e // Equivalent with $DVT_PROJECT_LOC/top1.e
-F other/file.f

-------- In other/file.f --------
// $MYVAR is used here to specify a path, '.' shall be solved to $DVT_PROJECT_LOC/other/
$MYVAR/top2.e // Equivalent with $DVT_PROJECT_LOC/other/top2.e

Predefined environment variables

Variable	Value
DVT_PROJECT_LOC	Absolute path of the project directory.