tvservice -s is giving wrong resolution - Raspberry Pi Forums

hi, have problem detecting resolution of plugged in monitor (i trying detect whether monitor plugged @ use in app in python), have tried

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tvservice -s

giving me wrong answers:
when hdmi unplugged @ booting:

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state 0x120016 [dvi dmt (4) rgb full 4:3], 640x480 @ 60.00hz, progressive

when hdmi plugged after that:

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state 0x120016 [dvi dmt (4) rgb full 4:3], 640x480 @ 60.00hz, progressive

(i expecting information hdmi not being plugged)

when hdmi plugged @ booting:

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state 0x120016 [dvi dmt (58) rgb full 16:10], 1680x1050 @ 60.00hz, progressive

when hdmi unplugged after

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state 0x120016 [dvi dmt (58) rgb full 16:10], 1680x1050 @ 60.00hz, progressive

main goal check whether hdmi monitor plugged

if nothing detected on hdmi port @ boot, defaults vga. matches seeing.

can not extract resolution tvservice using awk or similar? , if 640x480, assume it's not connected?

raspberrypi