Docs: send-email usage text much sexier
[git/jrn.git] / run-command.h
blob4f2b7d7d403ee6d87fea5ba2dc32da7596965e5e
1 #ifndef RUN_COMMAND_H
2 #define RUN_COMMAND_H
4 enum {
5 ERR_RUN_COMMAND_FORK = 10000,
6 ERR_RUN_COMMAND_EXEC,
7 ERR_RUN_COMMAND_PIPE,
8 ERR_RUN_COMMAND_WAITPID,
9 ERR_RUN_COMMAND_WAITPID_WRONG_PID,
10 ERR_RUN_COMMAND_WAITPID_SIGNAL,
11 ERR_RUN_COMMAND_WAITPID_NOEXIT,
14 struct child_process {
15 const char **argv;
16 pid_t pid;
18 * Using .in, .out, .err:
19 * - Specify 0 for no redirections (child inherits stdin, stdout,
20 * stderr from parent).
21 * - Specify -1 to have a pipe allocated as follows:
22 * .in: returns the writable pipe end; parent writes to it,
23 * the readable pipe end becomes child's stdin
24 * .out, .err: returns the readable pipe end; parent reads from
25 * it, the writable pipe end becomes child's stdout/stderr
26 * The caller of start_command() must close the returned FDs
27 * after it has completed reading from/writing to it!
28 * - Specify > 0 to set a channel to a particular FD as follows:
29 * .in: a readable FD, becomes child's stdin
30 * .out: a writable FD, becomes child's stdout/stderr
31 * .err > 0 not supported
32 * The specified FD is closed by start_command(), even in case
33 * of errors!
35 int in;
36 int out;
37 int err;
38 const char *dir;
39 const char *const *env;
40 unsigned no_stdin:1;
41 unsigned no_stdout:1;
42 unsigned no_stderr:1;
43 unsigned git_cmd:1; /* if this is to be git sub-command */
44 unsigned stdout_to_stderr:1;
45 void (*preexec_cb)(void);
48 int start_command(struct child_process *);
49 int finish_command(struct child_process *);
50 int run_command(struct child_process *);
52 #define RUN_COMMAND_NO_STDIN 1
53 #define RUN_GIT_CMD 2 /*If this is to be git sub-command */
54 #define RUN_COMMAND_STDOUT_TO_STDERR 4
55 int run_command_v_opt(const char **argv, int opt);
56 int run_command_v_opt_cd(const char **argv, int opt, const char *dir);
59 * env (the environment) is to be formatted like environ: "VAR=VALUE".
60 * To unset an environment variable use just "VAR".
62 int run_command_v_opt_cd_env(const char **argv, int opt, const char *dir, const char *const *env);
65 * The purpose of the following functions is to feed a pipe by running
66 * a function asynchronously and providing output that the caller reads.
68 * It is expected that no synchronization and mutual exclusion between
69 * the caller and the feed function is necessary so that the function
70 * can run in a thread without interfering with the caller.
72 struct async {
74 * proc writes to fd and closes it;
75 * returns 0 on success, non-zero on failure
77 int (*proc)(int fd, void *data);
78 void *data;
79 int out; /* caller reads from here and closes it */
80 #ifndef __MINGW32__
81 pid_t pid;
82 #else
83 HANDLE tid;
84 int fd_for_proc;
85 #endif
88 int start_async(struct async *async);
89 int finish_async(struct async *async);
91 #endif