![](templates/subSilver/images/CCSLogo.jpg) |
![CCS C Software and Maintenance Offers](templates/subSilver/images/forumAd6.jpg) |
View previous topic :: View next topic |
Author |
Message |
rolox
Joined: 25 Dec 2014 Posts: 33
|
sprint(), format parameter via variable |
Posted: Thu Dec 25, 2014 5:04 pm |
|
|
Hello,
how can i pass a formatstring to sprintf() via a variable ?
it only seems to work with constant formatstrings :
Code: | //does not work
char result[10]
char aktformat[10]="%4.1w";
sprintf(result,aktformat,123);
// Outputs only the formatstring itself
// works :
sprintf(result,"%5.1w",123);
//outputs " 12.3" as expected
|
tried same snippet with MPLAB XC8 compiler - there it works - but don't really want to switch just because of this issue ...
any hints welcome
greetings
rolox
edit: spent some more time on "search" and found an explanation in a similar topic about 4 years ago, which makes it most likely that CCS did not change this behaviour since then ...i'll have to check to change to integer and use some "itoa" functionality instead |
|
![](templates/subSilver/images/spacer.gif) |
Ttelmah
Joined: 11 Mar 2010 Posts: 19368
|
|
Posted: Fri Dec 26, 2014 9:18 am |
|
|
The CCS sprintf/printf, does not support this.
The reason is simple. They only load the code components required, not everything. As soon as you switch to a 'variable' for the functions, they get bulkier, having to load all the parts....
However if you must use a variable, then the open source sprintf, translates quite easily:
<http://www.opensource.apple.com/source/ruby/ruby-67.6/ruby/sprintf.c>
and the small sprintf, is even easier (remember you need 'PASS_STRINGS=IN_RAM', and look at Mark's sscanf implementation in the code library for how to handle variable length arguments):
<http://www.menie.org/georges/embedded/printf.html>
I've used versions of both, but for customers, so I can't post them. |
|
![](templates/subSilver/images/spacer.gif) |
rolox
Joined: 25 Dec 2014 Posts: 33
|
|
Posted: Sat Dec 27, 2014 12:38 pm |
|
|
Hello, thx for quick reply ....just had a look at both versions, the second one is tiny - but as far as ic acn see, they do not support the CCS format type "%n.mw" , f.w "%5.1w" which would be the one i'd used most, in some variations like "%5.0w", "%5.1w", "%5.2w".
But even if this is the same Type of format, it will not be possible to change it during runtime - probably the solution is "diy" ;-) |
|
![](templates/subSilver/images/spacer.gif) |
Ttelmah
Joined: 11 Mar 2010 Posts: 19368
|
|
Posted: Sat Dec 27, 2014 3:44 pm |
|
|
Or just add the w format to the code. There is nothing terribly 'magic' about it.
Remember that you could sprintf to a string, without any decimal point, and then just use the string functions to add this at the location you require. |
|
![](templates/subSilver/images/spacer.gif) |
rolox
Joined: 25 Dec 2014 Posts: 33
|
|
Posted: Sun Dec 28, 2014 6:10 am |
|
|
you're absolutely right. I'm pretty new to CCS and try to use as much existing as possible - the difficulty is often to find the right time to stop searching and switch to writing it yourself :-)
Thanks a lot for pointing out the possibilities ! I'll have some time now ...it's heavily snowing here , preventing me from moving in front of the door .... |
|
![](templates/subSilver/images/spacer.gif) |
|
|
You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum
|
Powered by phpBB © 2001, 2005 phpBB Group
|