Re: [PATCH blktests 2/3] common/rc: add _echo() function to trace sysfs attribute writes

[Bart Van Assche <bvanassche@acm.org>]

On 5/13/26 7:05 AM, Daniel Wagner wrote:
> On Wed, May 13, 2026 at 08:23:25PM +0900, Shin'ichiro Kawasaki wrote:
>> +# Echo a value to a file. This wrapper is used to trace sysfs attribute writes
>> +# when the --cmd-trace option is enabled.
>> +_echo() {
>> +	echo "$1" > "$2"
>> +}
> 
> Stupid question, can't we override the echo function, something like this:
> 
> echo() {
>      builtin echo "$@"
>      builtin echo "$@" >> "/tmp/debug_log.txt"
> }

How can this work since the sysfs/debugfs/configfs attribute is not an
argument of the echo command?

Thanks,

Bart.