# tracing::dispatcher::set_global_default - Rust
API documentation for the Rust `set_global_default` fn in crate `tracing`.
Keywords: rust, rustlang, rust-lang, set_global_default

# Function tracing::dispatcher::set_global_default [−] [src]

    pub fn set_global_default(
        dispatcher: Dispatch
    ) -> Result<(), SetGlobalDefaultError>

Sets this dispatch as the global default for the duration of the entire program. Will be used as a fallback if no thread-local dispatch has been set in a thread (using `with_default`.)

Can only be set once; subsequent attempts to set the global default will fail. Returns `Err` if the global default has already been set.

⚠ ️Warning

    Warning: In general, libraries should not call
    set_global_default()! Doing so will cause conflicts when
    executables that depend on the library try to set the default later.