Enhance the output sync mode.

Create a new file, output.c, and collect functions that generate output there.
We introduce a new global context specifying where output should go (to stdout
or to a sync file), and the lowest level output generator chooses where to
write output based on that context.

This allows us to set the context globally, and all operations that write
output (including functions like $(info ...) etc.) will use it.

Removed the "--trace=dir" capability.  It was too confusing.  If you have
directory tracking enabled then output sync will print the enter/leave message
for each synchronized block.  If you don't want that, disable directory
tracking.

1 files changed, 3 insertions, 19 deletions

diff --git a/make.1 b/make.1
index df2a169..87ee42e 100644
--- a/make.1
+++ b/make.1
@@ -289,25 +289,9 @@ This is used to pretend that the commands were done, in order to fool
 future invocations of
 .BR make .
 .TP 0.5i
-.B \-\-trace\fR[=\fImode\fR]
-Print information about the commands invoked by
-.BR make .
-If
-.I mode
-is not specified or is
-.B rule
-information about the disposition of each target is printed.  If
-.I mode
-is
-.B dir
-then directory enter/leave trace statements are shown for each synchronized
-output segment (see
-.BR \-O ).
-If
-.I mode
-is
-.B none
-then no tracing is performed.
+.B \-\-trace
+Information about the disposition of each target is printed (why the target is
+being rebuilt and what commands are run to rebuild it).
 .TP 0.5i
 \fB\-v\fR, \fB\-\-version\fR
 Print the version of the