savehistory {utils} | R Documentation |
Load or save or display the commands history.
loadhistory(file = ".Rhistory") savehistory(file = ".Rhistory") history(max.show = 25, reverse = FALSE)
file |
The name of the file in which to save the history, or from which to load it. The path is relative to the current working directory. |
max.show |
The maximum number of lines to show. Inf will
give all of the currently available history. |
reverse |
logical. If true, the lines are shown in reverse order. Note: this is not useful when there are continuation lines. |
There are several history mechanisms available for the different R
consoles, which work in similar but not identical ways. Other uses of
R, in particular embedded uses, may have no history.
This works under the readline
and GNOME and MacOS X consoles,
but not if readline
is not available (for example, in batch use
or in an embedded application).
The readline
history mechanism is controlled by two environment
variables: R_HISTSIZE
controls the number of lines that are
saved (default 512), and R_HISTFILE
sets the filename used for
the loading/saving of history if requested at the beginning/end of a
session (but not the default for these functions). There is no limit
on the number of lines of history retained during a session, so
setting R_HISTSIZE
to a large value has no penalty unless a
large file is actually generated.
These variables are read at the time of saving, so can be altered
within a session by the use of Sys.putenv
.
If you want to save the history (almost) every session, you can put a
call to savehistory()
in .Last
.
## Not run: .Last <- function() if(interactive()) try(savehistory("~/.Rhistory")) ## End(Not run)