W
W. eWatson
I thought I'd put a page break, chr(12), character in a txt file I wrote
to skip to the top of the page. It doesn't work. Comments?
to skip to the top of the page. It doesn't work. Comments?
G
Grant Edwards
Yes, it does work.
W
W. eWatson
Apparently not with with my Brother 1440 laser printer. The character inGrant said:
NotePad.txt looks like a small rectangle, and on the printed page. Same
result HP C6180 Photosmart.
T
Tim Chase
W. eWatson said:
But are you sending the raw control codes to the printer, or are
you sending the image-of-my-text-document to a printer-GDI which
then renders the as-you-see-it out of the printer?
The pseudo-pipeline comparison would be
type file.txt > lpt1:
which would send the raw text file to the printer (assuming it's
set up on LPT1, otherwise, use whatever port it's attached to in
your printer control panel); or are you using something like
notepad file.txt
File -> Print
which renders to an internal image representation and then sends
that image out to the printer. If it were a dot-matrix printer,
you'd here/see the difference in a jiffy -- the raw dump is fast
and uses the printer's built-in fonts while the render-as-image
is slow and NOISY.
One alternative is possibly to set up the "Generic Text" printer
as a device type and attach it to the same port; I've had fair
fortune with this letting me control the printer more directly if
I want fast dumps (particularly on dot-matrix printers) rather
than pretty dumps.
-tkc
W
W. eWatson
I should mention I'm using Windows. I just put chr(12) right in the txt.Tim said:
It's the first character in the next line of the txt file where I want
to page forward. Not acquainted with GDI. Maybe I need some sequence of
such characters?
T
Tim Chase
W. eWatson said:
It's not a matter of you controlling the GDI stuff. Unless
you're writing directly to the printer device, printing on
Windows is done (whether by Notepad, gvim, Word, Excel, whatever)
into a graphical representation which is then shipped off to the
printer. So if you're printing from Notepad, it's going to print
what you see (the little square), because Notepad renders to this
graphical representation to print. If you send the file
*directly* to the printer device (bypassing the Win32 printing
layer), it will send the ^L directly and should eject a new page
on most printers.
-tkc
W
W. eWatson
I am writing a txt file. It's up to the user to print it using NotepadTim said:
or some other tool. I have no idea how to send it directly to the
printer, but I really don't want to furnish that capability in the
program. From Google, The Graphics Device Interface (GDI).
M
Mensanator
Have you considered the possibility that your printer can't print
raw text files? I had one that would ONLY print Postscript. Embedding
a chr(12) would accomplish nothing, you HAD to use a driver that
would translate chr(12) into the appropriate Postcript codes.
What you're doing MIGHT work for others with different printers.
N
Neil Hodgson
W. eWatson said:
WordPad will interpret chr(12) as you want.
Neil
T
Tim Chase
W. eWatson said:
If you're writing it to a text file and assuming that Notepad is
smart enough to properly handle form-feeds, I'm sorry, you'll be
disappointed...this says more about the brain-deadness of Notepad
than your optimism
If you have a configurable destination, you might be able to do
something within your Python app like
if 'win' in sys.platform.lower():
default_dest = "lpt1:"
else:
default_dest = "/dev/lp0"
dest = config.get("printer", default_dest)
f = file(dest, 'wb')
f.write(my_output_with_ff)
# optionally
# f.write(chr(12))
# to eject the last page
f.close()
Otherwise, you'd have to write to something a default Windows
application would know how to handle with embedded
form-feeds/page-breaks (i.e., not Notepad as the default .txt
handler). My first thought would be to export it as RTF (there
was a good python RTF library I tinkered with one afternoon --
it's a quick google away) which should allow embedding
page-breaks, and even give you a fair bit of additional control
over other aspects like fonts and styles.
-tkc
W
W. eWatson
Could be, but I have no way of easily knowing. In any case, I was tryingMensanator said:
to write a simple report that could be printed with titles at the top of
each page. If there's another "common" format that I can write in to
produce the file, that's fine. It may be this is so difficult to be
impossible. Long, long ago this was no problem.
I suppose I could copy the txt file into wordpad, and print it there.
N
Nobody
The 1970's are over, and neither Notepad nor your printer attempts to
maintain compatibility with a Teletype model 37.
W
W. eWatson
Neil said:
That may be the solution. Just tell the end user to copy the file into
it, and print it there.
I just tried it in Wordpad, and it works, but my --- underlines are
pushed together. Maybe tabs instead of spaces. The columns past Seq # in
WordPad may suffer from the characters not being fixed width. Well, a
little work with WordPad might be enough for users to get it right.
"Copy txt file into wordpad. Select all the text, and set format to
fixed (if that's possible.).
Here's what a txt sample looks like. It has line wrap here, and the page
feed
Date/Time & Station UTC Seq # Frames Time Span Pix
Dst Pix/Sec
------------------- -- ------------------- ----- ------ ---------
------- -------
2008/11/12 17:38:58 WW 2008/11/13 01:38:58 1 Noise data. Short
track.
2008/11/12 17:39:24 WW 2008/11/13 01:39:24 2 Noise data. Short
track.
<-------------PAGE FEED
Date/Time & Station UTC Seq # Frames Time Span Pix
Dst Pix/Sec
------------------- -- ------------------- ----- ------ ---------
------- -------
2008/11/17 22:29:54 WW 2008/11/18 06:29:54 21 Noise data. Short
track.
2008/11/18 01:51:36 WW 2008/11/18 09:51:36 22 Noise data. Short
track.
2008/11/18 04:05:03 WW 2008/11/18 12:05:03 23 Noise data. Short
track.
2008/11/18 17:40:42 WW 2008/11/19 01:40:42 24 95 3.17
48.17 15.21
D
D'Arcy J.M. Cain
Could be, but I have no way of easily knowing. In any case, I was trying
to write a simple report that could be printed with titles at the top of
each page. If there's another "common" format that I can write in to
produce the file, that's fine. It may be this is so difficult to be
impossible. Long, long ago this was no problem.
Why not generate a PostScript or PDF file in the first place? Check
out reportlab.
W
W. eWatson
D'Arcy J.M. Cain said:
New Courier and NotePad produces a good looking result.
I'm trying to keep this effort to a minimum. I don't think tracking down
how to write PP code PDF code is worth for this effort.
In another related effort that I might get involved in, it would be good
to be able to produce graphical data as from MatPlotLib and be able to
print that to a printer directly from a Python program.
L
Lie Ryan
How about creating a new print job for each discontinuous page? AFAIK,
modern printer spooler don't continue printing between separate jobs? A
bit of hackery, but guaranteed to work unless you're using roll paper.
J
John Yeung
In another response, Tim Chase suggested creating an RTF file instead
of plain text. I think this is your best bet if your goal is to get
page breaks with the least amount of additional effort.
The package he's probably referring to is PyRTF. I took a quick look
at it and in my opinion it's overkill for your purposes. Since RTF is
actually just a markup language, and the only features of it that you
absolutely need are (1) a way to ensure a fixed-width font is used and
(2) a way to insert page breaks, it's probably quickest and simplest
to just throw the markup into the document yourself (well, with
Python) and naming the result with the .rtf suffix instead of .txt.
So, how do you find out what markup to use? Open WordPad, select the
font you want, type a bit of text, save the file as RTF (this should
be the default), and open up the file in Notepad. At the top will be
a bunch of setup codes, including the font selection. Make your
Python program put that whole spiel (including a trailing space or
newline, to separate your text from the last RTF tag) at the top of
your output. There will be one unmatched curly brace, which you
should close at the end of the document. On my computer, it looks
like this:
{\rtf1\ansi\ansicpg1252\deff0\deflang1033{\fonttbl{\f0\fmodern
\fprq1\fcharset0 Courier New;}}
{\*\generator Msftedit 5.41.15.1515;}\viewkind4\uc1\pard\f0\fs20
That takes care of the font (and other stuff, but you are interested
in the font). The only other things you need to do are put
r'\par' (the end-paragraph tag) at the end of each line and r'\page'
at the end of each page. Again, remember to make sure these tags
don't collide with your actual text. (I'd use '\\par\n' in place of
'\n' and '\\page\n' in place of chr(12).) Finally, make sure to end
with a closing curly brace as previously mentioned.
The RTF solution is probably more robust than embedding chr(12) and
telling the user to use WordPad, especially since I saw someone report
on another forum that chr(12) doesn't always work even in WordPad (it
might be dependent on the version of WordPad, or the printer, or
whatever).
I am too lazy to have actually read any documentation on RTF, but it's
freely available on the Web should you need to reference it.
John
B
bartc
Nobody said:
Odd that TXT files under Windows still use the same 13 (carriage return), 10
(linefeed) and 9 (tab) codes that used to work on my ASR 33. So why not code
12 (formfeed)?
S
Steve Holden
Or unless you are printing to a production mailing system, and don'tLie said:
want job headers printed or interspersed jobs.
A client of mine just built a web site where output from queries could
be HTML, PDF (Piza and ReportLab) or CSV (just written out). It's not
that hard (though the code isn't open sourced I may be able to get them
to document an outline of the process, or let me (in my copious spare time).
regards
Steve
T
Tim Chase
John said:
Yes, John is correct -- it was PyRTF that I tinkered with (which
can be overkill if all you want to do is what John describes).
I'm not well versed in RTF, and he demonstrates:
even in his laziness, he helpfully provided a quick guide on how
to hand-create simple documents without the addition of a
full-blown RTF toolkit like PyRTF.
-tkc