Right. Postscript is a language created by Adobe for resolution
independent page layout. It was first used by Apple in laser printers
where the resolution had become so high that it was not reasonable to
download an entire bitmap for a page. Instead Postscript lets you define
objects such as a circle via a center point and a radius to make an "O"
or the like. Needless to say Postscript is a whole giant complex
language unto itself, groff knows how to create it and Preview knows how
to interpret it. Postscript is also what makes a PDF work under the
hood. PDF containers add things like fonts, images, indexing, links and
more but the basic page layout is postscript.
CB
On 2/9/12 10:07 AM, Paul Erkens wrote:
Hi CB,
And now this is clear as well. Thanks a bundle. So what groff does is take
man's output, in whatever format man outputs it, and then reformats that into
postscript, whatever that is. I'll be reading.
Paul.
On Feb 9, 2012, at 4:00 PM, Chris Blouch wrote:
Didn't see an answer yet so let me try.
1. man -t routes the output of the man page through groff which defaults to
making it into Postscript and then Jonathan piped that postscript into the OSX
Preview app. Gives you a nice formatted output in a more Mac friendly viewer.
2. I think most of your question will be answered if you do a "man open". The
open command opens some file just as though you had done an Command-O in the finder on
it. The -a modifier specifies which application to use to open the file and the -f option
tells it to read input from standard in rather than a file, which would be needed to
accept input from the pipe's output.
CB
On 2/9/12 6:11 AM, Paul Erkens wrote:
Hi Johnathan,
Looking at the command you gave:
man -t bash | open -a preview -f
I have 2 questions.
1. man bash or man -t bash. What is groff? From man, I don't become any wiser.
It seems that man -t bash, will have man pass its output to groff, rather than
to stout, while groff in turn, does pass it to stdout with a lot of
modifications. What is it that I see, when I enter man -t? Groff is a front end
for something else that I completely don't understand. Question here is: what
are you doing, using man -t?
2. The output from man, traveling through gruff by means of the man -t option,
is then piped into the preview command. So far so good. But what is the -f
preview option for? I googled a lot but where do you find the preview mac
command line options? Question here is: what is -f doing in preview?
I understand the -a switch for open. If this were not in place, then the open
command, a mac specific one I know now, would never know where to look. -a
Specifies to look inside the applications folder, wherever that resides. Can
you please answer my 2 questions above? It looks like each new answer poses
new questions, but that will settle down over time I hope.
Paul.
On Feb 9, 2012, at 4:10 AM, Jonathan C. Cohn wrote:
The prompt string is defined in the variable PS1 for the bourne shell. I
believe that bash (bourne again shell ) also uses this variable. Note: you
only need to set it, no need to export it to the environment.
First check to verify the shell you are running
echo$shell
then run a man page on the shell (if you want to get fancy , then code like the
below should bring up the man page in preview...
man -t bash | open -a preview -f
But then again, google can find man pages, and there is actually a option in Google
settings to indicate that you want a UNIX man page when you enter "man XXX" in
the google search bar.
Best wishes,
Jonathan C. Cohn
[email protected]
On Feb 8, 2012, at 8:54 AM, Paul Erkens wrote:
Dear list,
I am learning to change the terminal prompt. It now includes my machine name
and my user name, which is what I want to get rid of. I think that the prompt
is contained in an environment variable. I found that I can look at them by
using env without parameters, and that works. However, prompt is not in here.
Where do I need to look, to find the placeholders string that gives me my
prompt?
Paul.
--
You received this message because you are subscribed to the Google Groups
"MacVisionaries" group.
To post to this group, send email to [email protected].
To unsubscribe from this group, send email to
[email protected].
For more options, visit this group at
http://groups.google.com/group/macvisionaries?hl=en.
--
You received this message because you are subscribed to the Google Groups
"MacVisionaries" group.
To post to this group, send email to [email protected].
To unsubscribe from this group, send email to
[email protected].
For more options, visit this group at
http://groups.google.com/group/macvisionaries?hl=en.
--
You received this message because you are subscribed to the Google Groups
"MacVisionaries" group.
To post to this group, send email to [email protected].
To unsubscribe from this group, send email to
[email protected].
For more options, visit this group at
http://groups.google.com/group/macvisionaries?hl=en.
--
You received this message because you are subscribed to the Google Groups
"MacVisionaries" group.
To post to this group, send email to [email protected].
To unsubscribe from this group, send email to
[email protected].
For more options, visit this group at
http://groups.google.com/group/macvisionaries?hl=en.
