From: "Shawn O. Pearce" <spearce@xxxxxxxxxxx>
With this patch, in the 'start_command' function after forking
we now take care of stderr in the child process before stdout.
This way if 'start_command' is called with a 'child_process'
argument like this:
.err = -1;
.stdout_to_stderr = 1;
then stderr will be redirected to a pipe before stdout is
redirected to stderr. So we can now get the process' stdout
from the pipe (as well as its stderr).
Update documentation in 'api-run-command.txt' accordingly.
Signed-off-by: Christian Couder <chriscool@xxxxxxxxxxxxx>
---
Documentation/technical/api-run-command.txt | 7 ++++---
run-command.c | 14 +++++++-------
2 files changed, 11 insertions(+), 10 deletions(-)
The changes since the previous versions are:
- added documentation,
- added 'From: "Shawn O. Pearce" <spearce@xxxxxxxxxxx>',
- improved title.
diff --git a/Documentation/technical/api-run-command.txt b/Documentation/technical/api-run-command.txt
index dfbf9ac..c097f8b 100644
--- a/Documentation/technical/api-run-command.txt
+++ b/Documentation/technical/api-run-command.txt
@@ -111,9 +111,10 @@ stderr as follows:
.no_stdin, .no_stdout, .no_stderr: The respective channel is
redirected to /dev/null.
- .stdout_to_stderr: stdout of the child is redirected to the
- parent's stderr (i.e. *not* to what .err or
- .no_stderr specify).
+ .stdout_to_stderr: stdout of the child is redirected to its
+ stderr. This happens before stderr is itself
+ redirected. So stdout will follow stderr to wherever
+ it is redirected.
To modify the environment of the sub-process, specify an array of
string pointers (NULL terminated) in .env:
diff --git a/run-command.c b/run-command.c
index 743757c..44100a7 100644
--- a/run-command.c
+++ b/run-command.c
@@ -91,6 +91,13 @@ int start_command(struct child_process *cmd)
close(cmd->in);
}
+ if (cmd->no_stderr)
+ dup_devnull(2);
+ else if (need_err) {
+ dup2(fderr[1], 2);
+ close_pair(fderr);
+ }
+
if (cmd->no_stdout)
dup_devnull(1);
else if (cmd->stdout_to_stderr)
@@ -103,13 +110,6 @@ int start_command(struct child_process *cmd)
close(cmd->out);
}
- if (cmd->no_stderr)
- dup_devnull(2);
- else if (need_err) {
- dup2(fderr[1], 2);
- close_pair(fderr);
- }
-
if (cmd->dir && chdir(cmd->dir))
die("exec %s: cd to %s failed (%s)", cmd->argv[0],
cmd->dir, strerror(errno));
--
1.5.4.3.395.g492b.dirty
--
To unsubscribe from this list: send the line "unsubscribe git" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
