How to redirect Valgrind's output to a file?
RedirectValgrindRedirect Problem Overview
While working with Valgrind tool, i need to log the details produced by valgrind tool. How can I accomplish that? I tried something like,
valgrind a.out | test
and
valgrind a.out > test
It gave just the program's output and not the valgrind memory error,leak information. Even i am getting like this if the program requires no user interaction (i.e. giving input). If the program need user input even that thing itself won't work.
How can I do this?
Redirect Solutions
Solution 1 - Redirect
valgrind --log-file="filename"
Solution 2 - Redirect
By default, Valgrind writes its output to stderr. So you need to do something like:
valgrind a.out > log.txt 2>&1
Alternatively, you can tell Valgrind to write somewhere else; see http://valgrind.org/docs/manual/manual-core.html#manual-core.comment (but I've never tried this).
Solution 3 - Redirect
You can also set the options --log-fd if you just want to read your logs with a less. For example :
valgrind --log-fd=1 ls | less
Solution 4 - Redirect
In addition to the other answers (particularly by Lekakis), some string replacements can also be used in the option --log-file=
as elaborated in the Valgrind's user manual.
Four replacements were available at the time of writing:
%p
: Prints the current process IDvalgrind --log-file="myFile-%p.dat" <application-name>
%n
: Prints file sequence number unique for the current processvalgrind --log-file="myFile-%p-%n.dat" <application-name>
%q{ENV}
: Prints contents of the environment variableENV
valgrind --log-file="myFile-%q{HOME}.dat" <application-name>
%%
: Prints%
valgrind --log-file="myFile-%%.dat" <application-name>