USB mont sometime failed

[SigmaTec]

Hi all,

I developed an Lua script which writes "csv" files on a USB 2.0 key.
This cyclic script performs regular "mount / umount" (every 6 hours) to guarantee the maximum number of correct files in the event of micro power cuts. 

It works fine, but I have random errors on the mount as : "mounting / dev / sda1 on / mnt failed: no such file or directory".

Do you have any explanations for this problem?

Than'k in advance for your help !


--- here is the umout/mount standard script I user ---

Code:

devs = io.ls('/sys/class/block/')


table.sort(devs)
for _, dev in ipairs(devs) do
  if dev:match('^sd%a%d$') then
    part = dev
    break
  elseif not devn and dev:match('^sd%a$') then
    devn = dev
  end
end

part = part or devn
if part then
  os.execute('umount -f /mnt 2>&-')
  res, stat = io.readproc('mount /dev/' .. part .. ' /mnt 2>&1')
  if stat == 0 then
    alert('USB mount OK')
  else
    alert('USB mount failed: ' .. tostring(res))           -----------> this line returns the random errors...
  end
else
  alert('No valid USB devices found')
end