stupid " & ' question

Xeratul · 05-27-2007, 06:22 PM

Quote:

scrot "/home/xeratul/shots/$(gdialog --title 'Screenshot' --inputbox 'Output filename:' 100 100).png"

this is absolutely not working and not makign its screenshot ...

I am fighting with the ' and ". It is very stupid but It cannot work. Why ?

Thank you

kstan · 05-27-2007, 07:39 PM

try this
scrot "/home/xeratul/shots/$(gdialog --title \'Screenshot\' --inputbox \'Output filename:\' 100 100).png"
or
scrot /home/xeratul/shots/$(gdialog --title 'Screenshot' --inputbox 'Output filename:' 100 100).png
if still doesn't work, try to issue filename without a space.

Regards,
Ks

jschiwal · 05-27-2007, 09:49 PM

The gdialog part of the command is OK. The problem is that gdialog returns its value on stderr instead of stdout.

Try the command by itself and then with 2&>/dev/null. During the latter, there is no output.

Code:

gdialog --title 'Screenshot' --inputbox 'Output filename:' 100 100
sample2
gdialog --title 'Screenshot' --inputbox 'Output filename:' 100 100 2&>/dev/null

However, this could be due to gdialog being a wrapper command for zenity. When I went to install gdialog, I was able to install zenity.

That said, I was able to do this:

Code:

filename=$(zenity --title 'Screenshot' --entry 'Output filename:' 100 100 | cat).png
scrot "$filename"
and this:
scrot $(gdialog --title 'Screenshot' --inputbox 'Output filename:' 100 100 2&>/dev/stdout).png

Xeratul · 05-28-2007, 01:11 AM

Quote:

Originally Posted by jschiwal

The gdialog part of the command is OK. The problem is that gdialog returns its value on stderr instead of stdout.

Try the command by itself and then with 2&>/dev/null. During the latter, there is no output.

Code:

gdialog --title 'Screenshot' --inputbox 'Output filename:' 100 100
sample2
gdialog --title 'Screenshot' --inputbox 'Output filename:' 100 100 2&>/dev/null

However, this could be due to gdialog being a wrapper command for zenity. When I went to install gdialog, I was able to install zenity.

That said, I was able to do this:

Code:

filename=$(zenity --title 'Screenshot' --entry 'Output filename:' 100 100 | cat).png
scrot "$filename"
and this:
scrot $(gdialog --title 'Screenshot' --inputbox 'Output filename:' 100 100 2&>/dev/stdout).png

Thank you !

Indeed, the single function:

Code:

scrot "screenshots/$(gdialog --title 'Screenshot' --inputbox 'Output filename:' 100 100 2&>/dev/stdout).png"

works.

I looked on:
http://en.wikipedia.org/wiki/Image:S...ms-notitle.svg
http://www.phim.unibe.ch/comp_doc/c_.../stdfiles.html
http://www.faqs.org/faqs/unix-faq/fa...section-9.html
to understand how to find out if a program is stdout.

I am not sure to understand why it is stderr (reason) and how to detect the output whether they are stdout only or stderr...

No so easy all these stderr/stdout ...

Xeratul · 05-28-2007, 07:16 AM

Soo, I tried to use the /dev/null stuffs

I have a folder containing 10 files.

Why this is not working then ... ?

Code:

 for each in "$(ls -1)" ;   do   beep > /dev/null      ; sleep 3  ; done

Code:

 for each in "$(ls -1)" ;   do   eog $each > /dev/null      ; sleep 3  ; done

are both not working

That s not easy to learn sh, it s not like basic. Really complex guy.

Thank you greatly if you find out the problem ?!

==
is working:

Code:

  for each in "$(ls -1)" ;   do   ls -la $each    ; sleep 3  ; done

===
your trick, let open only one single file :-( (at least):

Code:

 for each in "$(ls -1)" ;   do   eog $each&  &>/dev/stdout   ; done

Xeratul · 05-28-2007, 07:42 AM

I found the error :

for FILE in $(ls); do [COMMAND]; done

This ; is very importnat apparently

==
howto:
http://penguinpetes.com/b2evo/index....&c=1&tb=1&pb=1.

Xeratul · 05-28-2007, 07:45 AM

Very interesting:

why ?

this works:

Code:

for FILE in $(ls); do echo $FILE ; beep ; done

and this not

Code:

for FILE in "$(ls)"; do echo $FILE ; beep ; done

because the "" will consider only one file
damn

jschiwal · 05-28-2007, 08:45 AM

Quote:

Originally Posted by Xeratul

Very interesting:

why ?

this works:

Code:

for FILE in $(ls); do echo $FILE ; beep ; done

and this not

Code:

for FILE in "$(ls)"; do echo $FILE ; beep ; done

because the "" will consider only one file
damn

You don't need the ls command:
for file in *
will do fine. You don't put quotes around the term when using for, but when you reference the variable, it is a good idea if any of the filenames contain embedded whitespace
for file in *; do
dosomething "$file"
done

---

I don't understand why gdialog returns the output on stderr. The manpage says differently. However in my case, I don't actually have the gdialog command. Mine is a perl script wrapper which calls the zenity command.

In your script if you have zenity as well you could use
"zenity --file-selection" instead.

Xeratul · 05-29-2007, 01:56 PM

Quote:

Originally Posted by jschiwal

You don't need the ls command:
for file in *
will do fine. You don't put quotes around the term when using for, but when you reference the variable, it is a good idea if any of the filenames contain embedded whitespace
for file in *; do
dosomething "$file"
done

---

I don't understand why gdialog returns the output on stderr. The manpage says differently. However in my case, I don't actually have the gdialog command. Mine is a perl script wrapper which calls the zenity command.

In your script if you have zenity as well you could use
"zenity --file-selection" instead.

a perl or python program or the xdialog would be maybe a better solution, that wouldnt call the gnome environment and would be lighter in terms of memory consumtion ... I guess, no ?

thank you for yoru help with this *
that solved indeed the \ problems with space !!