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environment variable

A named setting the operating system hands to every program it starts, like PATH.

Environment variables are name=value strings inherited by each process from its parent; Rust reads them with std::env::var and a child process inherits them unless changed.

Examples

  • RUST_BACKTRACE=1 cargo run sets one environment variable for that run, so a panic prints a backtrace.

See also

PATH variable backtrace configuration precedence
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