On Thu, Jan 07, 2016 at 08:56:06PM +0000, Reuben Thomas wrote:
[...]
> Yes, and it's not at the moment (or wasn't, until I added timestamps to
> every line in my history), because the lines at the start of the history,
> with no timestamp, were given the current date and time, and lines at the
> end of the history, with timestamps, were given the earlier date and time
> at which they were added to the history. That's why the epoch is better.
> Also, it's a better clue that the timestamp is being faked.
I now understand your points.
I was playing a bit with the code, and found the piece that initializes time in
history entries:
dualbus@hp ...src/gnu/bash % git diff
diff --git a/lib/readline/history.c b/lib/readline/history.c
index 3b8dbc5..2b186e9 100644
--- a/lib/readline/history.c
+++ b/lib/readline/history.c
@@ -258,7 +258,7 @@ hist_inittime ()
time_t t;
char ts[64], *ret;
- t = (time_t) time ((time_t *)0);
+ t = (time_t) 1;
#if defined (HAVE_VSNPRINTF) /* assume snprintf if vsnprintf
exists */
snprintf (ts, sizeof (ts) - 1, "X%lu", (unsigned long) t);
#else
But it seems that the fix is not that simple, since now this happens:
dualbus@hp ...src/gnu/bash % cat ~/.bash_history
echo 1
#1452197044
echo a; sleep 1
#1452197045
echo b; sleep 1
dualbus@hp ...src/gnu/bash % ./bash -i <<<
"HISTTIMEFORMAT='%Y-%m-%dT%H:%M:%S ' history"
dualbus@hp:~/local/src/gnu/bash$ HISTTIMEFORMAT='%Y-%m-%dT%H:%M:%S ' history
1 1969-12-31T18:00:01 echo 1
2 2016-01-07T14:04:04 echo a; sleep 1
3 2016-01-07T14:04:05 echo b; sleep 1
4 1969-12-31T18:00:01 HISTTIMEFORMAT='%Y-%m-%dT%H:%M:%S ' history
So, it seems that new entries are created with the localtime, unless there's a
history comment followed by a timestamp. I'm not sure what changes are needed
to adjust this, but I guess that is not a simple fix.
BTW, the timestamp = 0 thing is a bug in readline. Since it uses (time_t) 0 as
a return value for errors in history_get_time, and later there's code similar
to this:
t = history_get_time(...)
if(t)
strftime(...)
else
strcat(..., "??")
It considers 0 as an invalid value.
--
Eduardo Bustamante
https://dualbus.me/
