It maybe when using a windows utility…
The correct address when mounted on the emonSD’d OS is
/home/pi/data/wpa_supplicant.conf Glyn’s reference of
~/data/wpa_supplicant.conf uses “~” which is a linux shortcut for “the current users home/root directory” which only when accessed via the emonSD by user pi will be
Since the 3rd partition is mounted as
/home/pi/data that is the most accurate path whilst mounted ie via the emonSD OS.
data is an
ext2 linux partition, when using a “windows reader utility” to read the linux partition, it is not writable. However it is writable when mounted in a linux OS. The windows readers tend to make a copy of the file that windows can read, in which case any edits will be to a windows only copy file and not to the original linux file, so no change when you put the card back in the emonpi.
The ONLY way of doing it with “windows only” is to put the file on the
boot partition, it is the only partition that is recognized by both linux and windows, that is the reason it exists.
This is always good advice, more so when editing the emonSD as it’s difficult to predict what may change. But since the wpa_supplicant.conf cannot be “just overwritten” by the emonpi updater deleting and replacing it without losing users wifi settings, it is unlikely this move will prevent future updates. The one time I would predict trouble would be IF the OS was writable and a wpa_supplicant.conf file was accidentally added to the boot partition before a reboot, since the OS is RO and this function doesn’t work, this is unlikely to happen.
Any move from “stock” emonSD could comeback and bite you. But it is the only way to do this without a 2nd linux OS (VM or Pi etc) AFAICT.