From 0b91322311b649a4b5f9581fec2dca9e1c2da716 Mon Sep 17 00:00:00 2001 From: Johannes Sixt Date: Sat, 8 Aug 2009 22:44:20 +0200 Subject: api-run-command.txt: describe error behavior of run_command functions Signed-off-by: Johannes Sixt Signed-off-by: Junio C Hamano --- Documentation/technical/api-run-command.txt | 31 ++++++++++++++++++++++++++--- 1 file changed, 28 insertions(+), 3 deletions(-) (limited to 'Documentation/technical') diff --git a/Documentation/technical/api-run-command.txt b/Documentation/technical/api-run-command.txt index 2efe7a40be..b26c28133c 100644 --- a/Documentation/technical/api-run-command.txt +++ b/Documentation/technical/api-run-command.txt @@ -35,12 +35,32 @@ Functions Convenience functions that encapsulate a sequence of start_command() followed by finish_command(). The argument argv specifies the program and its arguments. The argument opt is zero - or more of the flags `RUN_COMMAND_NO_STDIN`, `RUN_GIT_CMD`, or - `RUN_COMMAND_STDOUT_TO_STDERR` that correspond to the members - .no_stdin, .git_cmd, .stdout_to_stderr of `struct child_process`. + or more of the flags `RUN_COMMAND_NO_STDIN`, `RUN_GIT_CMD`, + `RUN_COMMAND_STDOUT_TO_STDERR`, or `RUN_SILENT_EXEC_FAILURE` + that correspond to the members .no_stdin, .git_cmd, + .stdout_to_stderr, .silent_exec_failure of `struct child_process`. The argument dir corresponds the member .dir. The argument env corresponds to the member .env. +The functions above do the following: + +. If a system call failed, errno is set and -1 is returned. A diagnostic + is printed. + +. If the program was not found, then -1 is returned and errno is set to + ENOENT; a diagnostic is printed only if .silent_exec_failure is 0. + +. Otherwise, the program is run. If it terminates regularly, its exit + code is returned. No diagnistic is printed, even if the exit code is + non-zero. + +. If the program terminated due to a signal, then the return value is the + signal number - 128, ie. it is negative and so indicates an unusual + condition; a diagnostic is printed. This return value can be passed to + exit(2), which will report the same code to the parent process that a + POSIX shell's $? would report for a program that died from the signal. + + `start_async`:: Run a function asynchronously. Takes a pointer to a `struct @@ -143,6 +163,11 @@ string pointers (NULL terminated) in .env: To specify a new initial working directory for the sub-process, specify it in the .dir member. +If the program cannot be found, the functions return -1 and set +errno to ENOENT. Normally, an error message is printed, but if +.silent_exec_failure is set to 1, no message is printed for this +special error condition. + * `struct async` -- cgit v1.2.3