cuos/process.h: Running external processes
[cuos: Interface to the Operating System]

Functions
pid_t	cuos_start_prog_fd (char const *prg, char const *const *argv, char *const *envp, int *fd_arr)
pid_t	cuos_start_prog_io (char const *prg, char const *const *argv, char *const *envp, FILE **in, FILE **out, FILE **err)
pid_t	cuos_start_prog (char const *prg, char const *const *argv, char *const *envp)
int	cuos_wait_for_prog (char const *prg, pid_t pid)
int	cuos_call_prog (char const *prg, char const *const *argv, char *const *envp)
int	cuos_call_prog_fd (char const *prg, char const *const *argv, char *const *envp, int *fd_arr)
void	cuos_argv_cct_strlist (char const **argv, cucon_list_t strlist)
cu_str_t	cuos_shell_escape_cstr (char const *cstr)
void	cuos_argv_fprint (char const **argv, FILE *out)

---

Function Documentation

void cuos_argv_cct_strlist	(	char const **	argv,
		cucon_list_t	strlist
	)

Construct a NULL terminated argv from a cucon_list_t of cu_str_t. argv must have at least cucon_list_count (strlist) + 1 elements.

void cuos_argv_fprint	(	char const **	argv,
		FILE *	out
	)

Print out argv to out.

int cuos_call_prog	(	char const *	prg,
		char const *const *	argv,
		char *const *	envp
	)

Start in a sub-process and wait for the program prg with arguments argv and environment envp. See cuos_start_prog for details.

int cuos_call_prog_fd	(	char const *	prg,
		char const *const *	argv,
		char *const *	envp,
		int *	fd_arr
	)

Start in a sub-process and wait for the program prg with arguments argv, environment envp and redirections fd_arr. See cuos_start_prog_fd for details.

cu_str_t cuos_shell_escape_cstr

(

char const *

cstr

)

Returns 'cstr' with shell special chars (including space) escaped. May quote more than strictly needed.

pid_t cuos_start_prog	(	char const *	prg,
		char const *const *	argv,
		char *const *	envp
	)

Shortcut for cuos_start_prog_fd when no redirections are needed.

pid_t cuos_start_prog_fd	(	char const *	prg,
		char const *const *	argv,
		char *const *	envp,
		int *	fd_arr
	)

Fork the current process and call

 execvp(prg, argv)

in the subprocess. If fd_arr is not NULL, redirect file descriptor i to fd_arr[i] iff fd_arr[i] ≠ -1. The given file descriptors will be closed by this function. The process id is returned.

• fd_arr[0] file descriptor for stdin in the subprocess, or -1
• fd_arr[1] file descriptor for stdout in the subprocess, or -1
• fd_arr[2] file descriptor for stderr in the subprocess, or -1

pid_t cuos_start_prog_io	(	char const *	prg,
		char const *const *	argv,
		char *const *	envp,
		FILE **	in,
		FILE **	out,
		FILE **	err
	)

Fork the current process and call

 execvp(prg, argv)

in the subprocess. For each in, out, err which is non-NULL, return an open file to the stdin, stdout, stderr of the subprocess. Note that stdin is opened for writing and the others are opened for reading.

int cuos_wait_for_prog	(	char const *	prg,
		pid_t	pid
	)

Wait for the process with process id pid as retured by cuos_start_prog_fd, cuos_start_prog_io, or cuos_start_prog. prg should be the same as the first argument of the corresponding start-function.