Help de Toulousain!
time -o fichier command
man time :
NAME
time - time command execution
SYNOPSIS
time [-alp] [-o file] command
DESCRIPTION
The time utility executes and times command by initiating a timer and
passing the command to the shell. After the command finishes, time
writes to the standard error stream, (in seconds): the total time
elapsed, the time used to execute the command process and the time con-
sumed by system overhead.
Available options:
-a If the -o flag is used, append to the specified file rather than
overwriting it. Otherwise, this option has no effect.
-l The contents of the rusage structure are printed as well.
-o file
Write the output to file instead of stderr. If file exists and
the -a flag is not specified, the file will be overwritten.
-p Makes time output POSIX.2 compliant (each time is printed on its
own line).
Most shells (including csh(1)) have their own and syntactically differ-
ent builtin version of time. The command described here is available as
/usr/bin/time to users of those shells.
DIAGNOSTICS
If command could be timed successfully, its exit status is returned. In
case command terminated abnormally, a warning message is output to
stderr. If the command was found but could not be run, the exit status
is 126. If no command could be found at all, the exit status is 127. If
time encounters any other error, the exit status is between 1 and 125 in-
cluded.
SEE ALSO
csh(1), getrusage(2), wait(2)