[Toybox] [PATCH] Fix more to a non-tty.

[enh]

On Sat, Apr 23, 2016 at 8:41 PM, Rob Landley <rob at landley.net> wrote:
> On 04/23/2016 04:40 PM, enh wrote:
>> On Sat, Apr 23, 2016 at 12:39 PM, Rob Landley <rob at landley.net> wrote:
>>> On 04/21/2016 07:42 PM, enh wrote:
>>>> And add a test.
>>>> ---
>>>>  toys/pending/more.c | 2 +-
>>>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>>
>>> Applied, but I don't see the test?
>>
>> d'oh. fooled by git commit -a yet again.
>>
>>> Sigh: I wanted "more" and "less" to share code, but they really don't do
>>> the same thing (random example: "ls --color | more" vs "ls --color | less").
>>
>> there's "less -r". but i didn't know that until i read the help just now :-)
>
> And this implementation of more has approximately the same problem that
> less -r's man entry documents about keeping track of where it is on the
> screen:
>
>       putchar(ch);
>       if (ch == '\t') col = (col | 0x7) + 1;
>       else col++;
>       if (col == cols) putchar(ch = '\n');
>       if (ch == '\n') {
>
> That treats the ansi escapes as normal printing characters for
> determining when the screen wraps, in which case this inserts a
> gratuitous newline (instead of allowing the screen to wrap itself)...
>
> The posix more spec says it gets the screen height from -n or an
> environment variable and if neither are set it uses an _unspecified_
> number of lines. Actually querying your terminal size is nonstandard
> behavior. Lovely.
>
>> having more(1) be the simplest possible thing probably best matches
>> the intentions of anyone who deliberately chooses more(1) over less(1)
>> anyway.
>
> We have two lines of colons instead of one when announcing a new file. I
> can't find ANY reference to a line of colons in the posix thing,

i had no idea there was a POSIX more(1). or that it's more like
less(1) than any real more(1). (the only obviously annoying thing is
that they say ' ' should behave like '\n', rather than keeping the
page vs line behavior that both more(1) and less(1) have in real
life.)

your earlier comments about sharing with less/vi make a lot more sense
in the context of the hypothetical POSIX more(1) :-)

> the
> closest I can find is this bit of the extended description:
>
>> For all files but the last (including standard input if no file was
>> specified, and for the last file as well, if the -e option was not
>> specified), when more has written the last line in the file, more
>> shall prompt for a user command. This prompt shall contain the name
>> of the next file as well as an indication that more has reached
>> end-of-file. If the user command is f, <control>-F, <space>, j,
>> <newline>, d, <control>-D, or s, more shall display the next file.
>> Otherwise, if displaying the last file, more shall exit. Otherwise,
>> more shall execute the user command specified.
>
> Which says nothing about the format...
>
> Sigh. "Simple." Right...
>
> Rob



-- 
Elliott Hughes - http://who/enh - http://jessies.org/~enh/
Android native code/tools questions? Mail me/drop by/add me as a reviewer.