On Mon, Sep 02, 2013 at 10:37:45PM -0400, Dale R. Worley wrote: > > I've noticed that Git by default puts long output through "less" as a > > pager. I don't like that, but this is not the time to change > > established behavior. But while tracking that down, I noticed that > > the paging behavior is controlled by at least 5 things: > > > > the -p/--paginate/--no-pager options > > the GIT_PAGER environment variable > > the PAGER environment variable > > the core.pager Git configuration variable > > the build-in default (which seems to usually be "less") This list has some orthogonal concepts. The "-p" and "--no-pager" variables decide _whether_ to run the pager. The GIT_PAGER and PAGER environment variables, along with core.pager and the compile-time default, decide _which_ pager to run. The fact that "cat" or the empty string becomes "no pager" is purely an optimization (we could fork and run "sh -c ''" or "cat", but it would be a no-op). So even though you might have instructed git to run the pager, it may be a noop if your pager is "cat", and we optimize it out. The confusing one (and missing from your list) is pager.$program, which originally was a "whether", but later learned to optionally be a "which". And you also omit the built-in defaults for "whether" on each command (e.g., "log" runs a pager, "push" does not). > There is a somewhat independent question of when the pager is > activated. What I know so far is that some commands use the pager by > default and some by default do not. My expectation is that > --no-pager can be used to suppress the pager for *any* command. Is it > also true that -p can force the pager for *any* command, or are there > commands which will not page even with -p? Yes, --no-pager and -p suppress or force, respectively, for any command. They take precedence over config (pager.$command), which in turn takes precedence over builtin defaults (per-command defaults, in this case). Environment variables should generally be less than command-line options, but greater than config. But there is no "definitely use a pager" environment variable, so it doesn't apply here. And I say generally because we should put git-specific environment variables over git-specific config, but git-specific config over general environment variables (so similarly we should respect user.email in the config over $EMAIL in the environment, but under $GIT_COMMITTER_EMAIL). > I assume that if -p is specified but the "which pager" selection is > "cat" (or some other specification of no pager), then there is no > paging operation. There is a pager in that case, but it doesn't do anything. And then we optimize it out because it doesn't do anything. :) That is somewhat tongue-in-cheek, but I hope it shows the mental model that goes into the decision. -Peff -- 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