env ';' KEY (';' STRING)?

Summary

The env macro looks up an environment variable and returns its value, or returns a default value if the variable is not set. The default is an empty string if not specified.

Syntax

${env;<variable>[;<default>]}

Parameters

• variable - The environment variable name to look up
• default (optional) - Value to return if variable not set (default: empty string)

Behavior

• Looks up environment variable via System.getenv()
• Returns variable value if set
• Returns default if variable not set
• Default is empty string if not specified
• Case-sensitive on Unix/Linux, case-insensitive on Windows

Examples

Get environment variable with default:

${env;JAVA_HOME;/usr/lib/jvm/default}

Check if variable exists:

${if;${env;CI};running-in-ci;local-build}

Use in paths:

user.home=${env;HOME;/home/default}

Empty default:

${env;OPTIONAL_VAR}
# Returns value or "" if not set

Use Cases

• Accessing environment configuration
• CI/CD environment detection
• User-specific paths
• System configuration
• Platform differences
• Secure credentials (with caution)

Notes

• Accesses system environment variables
• Case sensitivity varies by OS
• Returns default for undefined variables
• Empty string is valid default
• Security: Be cautious with credentials
• See also: ${def} for properties
• See also: ${system} for system commands

See test cases in MacroTestsForDocsExamples.java