import type { HostSubprocess } from "../host.js";
/** The variables of an environment that have a value. `process.env` can
 *  hold undefined for a variable deleted with `delete`; a child's
 *  environment cannot. */
export declare function definedVariables(env: NodeJS.ProcessEnv): Record<string, string>;
/** The environment a shell script runs with: `env` without the variables
 *  above. */
export declare function shellEnvironment(env: Record<string, string>): Record<string, string>;
/** The first executable file named `program` in the folders of
 *  `searchPath`, or null. Synchronous because a shell script's spawn uses
 *  it, and `startChild` hands back `kill` before anything settles. A
 *  relative entry is skipped: it would resolve against the working
 *  directory, which an agent writes into. */
export declare function locateProgramSync(program: string, searchPath: string): string | null;
export declare const nodeSubprocess: HostSubprocess;