ENH check that important exes actually exist

conky.conf

@@ -69,7 +69,7 @@ local get_config_dir = function()
 end
 
 local try_config_paths = {
-   get_config_dir()..'conky.ymll',
+   get_config_dir()..'conky.yml',
    conky_dir..'config/fallback.yml'
 }
 

core

@@ -1 +1 @@
-Subproject commit 2924a6118d4fe30f3005800d65f6c378305f7c61
+Subproject commit ac2604709f5344125519913849e9013e1dfea717

drawing/filesystem.lua

@@ -10,6 +10,8 @@ return function(config, main_state, common, width, point)
    -----------------------------------------------------------------------------
    -- smartd
 
+   i_o.exe_assert('pidof')
+
    local mk_smart = function(y)
       local obj = common.make_text_row(point.x, y, width, 'SMART Daemon')
       local update = function()

drawing/graphics.lua

@@ -7,12 +7,15 @@ return function(update_freq, config, common, width, point)
    local PLOT_SEC_BREAK = 20
    local PLOT_HEIGHT = 56
    local NA = 'N/A'
+   local NVIDIA_EXE = 'nvidia-settings'
    local __string_match	= string.match
    local __tonumber = tonumber
 
    -----------------------------------------------------------------------------
    -- nvidia state
 
+   i_o.exe_assert(NVIDIA_EXE)
+
    -- vars to process the nv settings glob
    --
    -- glob will be of the form:
@@ -21,7 +24,8 @@ return function(update_freq, config, common, width, point)
    --   <temp>
    --   <gpu_freq>,<mem_freq>
    --   graphics=<gpu_util>, memory=<mem_util>, video=<vid_util>, PCIe=<pci_util>
-   local NV_QUERY = 'nvidia-settings -t'..
+   local NV_QUERY = NVIDIA_EXE..
+      ' -t'..
       ' -q UsedDedicatedGPUmemory'..
       ' -q TotalDedicatedGPUmemory'..
       ' -q ThermalSensorReading'..