#ifndef __SUBCMD_RUN_COMMAND_H#define __SUBCMD_RUN_COMMAND_H #include <unistd.h> enum {	ERR_RUN_COMMAND_FORK = 10000,	ERR_RUN_COMMAND_EXEC,	ERR_RUN_COMMAND_PIPE,	ERR_RUN_COMMAND_WAITPID,	ERR_RUN_COMMAND_WAITPID_WRONG_PID,	ERR_RUN_COMMAND_WAITPID_SIGNAL,	ERR_RUN_COMMAND_WAITPID_NOEXIT,};#define IS_RUN_COMMAND_ERR(x) (-(x) >= ERR_RUN_COMMAND_FORK) struct child_process {	const char **argv;	pid_t pid;	/*	 * Using .in, .out, .err:	 * - Specify 0 for no redirections (child inherits stdin, stdout,	 *   stderr from parent).	 * - Specify -1 to have a pipe allocated as follows:	 *     .in: returns the writable pipe end; parent writes to it,	 *          the readable pipe end becomes child's stdin	 *     .out, .err: returns the readable pipe end; parent reads from	 *          it, the writable pipe end becomes child's stdout/stderr	 *   The caller of start_command() must close the returned FDs	 *   after it has completed reading from/writing to it!	 * - Specify > 0 to set a channel to a particular FD as follows:	 *     .in: a readable FD, becomes child's stdin	 *     .out: a writable FD, becomes child's stdout/stderr	 *     .err > 0 not supported	 *   The specified FD is closed by start_command(), even in case	 *   of errors!	 */	int in;	int out;	int err;	const char *dir;	const char *const *env;	unsigned no_stdin:1;	unsigned no_stdout:1;	unsigned no_stderr:1;	unsigned exec_cmd:1; /* if this is to be external sub-command */	unsigned stdout_to_stderr:1;	void (*preexec_cb)(void);}; int start_command(struct child_process *);int finish_command(struct child_process *);int run_command(struct child_process *); #define RUN_COMMAND_NO_STDIN 1#define RUN_EXEC_CMD	     2	/*If this is to be external sub-command */#define RUN_COMMAND_STDOUT_TO_STDERR 4int run_command_v_opt(const char **argv, int opt); #endif /* __SUBCMD_RUN_COMMAND_H */