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This wrapper is used to trace sysfs attribute writes > > Echo -> Write > file -> sysfs/debugfs/configfs attribute > sysfs -> sysfs/debugfs/configfs Thanks, these descriptions are more accurate. > > +# when the --cmd-trace option is enabled. > > +_echo() { > > + echo "$1" > "$2" > > +} > > If this is only used to write into sysfs/debugfs/configfs, there are > probably better names for this function than _echo, e.g. _set_attr(), > _write_attr() or _write_sys_attr(). Agreed, _set_attr() sounds good to me. > > Should "echo" or "echo -n" be used in the above shell function? I couldn't catch the comment above. The current patch uses "echo", and it's working.