Hi,
Suppose I downloaded linux kernel.
When I run "make", many of the .c files will be compiled.
I want to know which .c files are compiles and which .c files are not compiled.
Is there any way to know in linux?
Access time of the files which are compiled is not getting modified
when I run "make" . why?
Thanks in advance.
Hi Ranjith,
On 02/13/2012 12:30 PM, ranjith kumar wrote:
> Hi,
> Suppose I downloaded linux kernel.
> When I run "make", many of the .c files will be compiled.
> I want to know which .c files are compiles and which .c files are not compiled.
> Is there any way to know in linux?
An easy way is to run your command with 'strace' to trap all the calls
to 'open':
strace make 2>&1 | grep open
>
> Access time of the files which are compiled is not getting modified
> when I run "make" . why?
That's correct. As long as you don't read these files, there's no reason
to update their latest access time. Comparing access time with modified
time is a useful way to know which files haven't been read after being
modified.
Cheers
Michael.
--
Michael Opdenacker, Free Electrons
Kernel, drivers, real-time and embedded Linux
development, consulting, training and support.
http://free-electrons.com
+33 484 253 396
On Mon, 13 Feb 2012 13:32:56 +0100, Michael Opdenacker said:
> An easy way is to run your command with 'strace' to trap all the calls
> to 'open':
>
> strace make 2>&1 | grep open
You really want 'strace -f make' - the -f flag makes it follow forks, which you
want to do because it's gcc that's doing most of the actual file I/O, not make.
Oh. and you want to redirect that grep into a temporary file and be
prepared to post-process it with perl or something, there's going to be
*zillions* of open() syscalls.
On 13.02.2012 23:44, [email protected] wrote:
> On Mon, 13 Feb 2012 13:32:56 +0100, Michael Opdenacker said:
>
> > An easy way is to run your command with 'strace' to trap all the calls
> > to 'open':
> >
> > strace make 2>&1 | grep open
>
> You really want 'strace -f make' - the -f flag makes it follow forks, which you
> want to do because it's gcc that's doing most of the actual file I/O, not make.
>
> Oh. and you want to redirect that grep into a temporary file and be
> prepared to post-process it with perl or something, there's going to be
> *zillions* of open() syscalls.
Inotify is certainly easier.
When inotifywait from inotify-tools is available:
inotifywait -m -r -e open <dir> > files.opened
This monitors recusivly for the "open" event and writes it into
files.opened.
In my case that is:
wc -l files.opened
1115553 files.opened
And this number of unique files with directories
sort < files.opened | uniq | wc -l
5454
And this number af unique fiels without dirs.
cat files.opened | grep -v ISDIR | sort | uniq | wc -l
3837
I use "O=../compile_dir" to get the output into another dir, if you
don't do that all newly created files are also counted, as you also
"open" them.
Bis denn
--
Real Programmers consider "what you see is what you get" to be just as
bad a concept in Text Editors as it is in women. No, the Real Programmer
wants a "you asked for it, you got it" text editor -- complicated,
cryptic, powerful, unforgiving, dangerous.