[paolog]

at the end I did a script to modify the gamma settings for Adobe and DjVu viewer, with the use of iv_shtool made by rkomar to have a graphic interface

https://www.mobileread.com/forums/sho...d.php?t=163556

below there is my code; I'm not a programmer so it's quite raw and naive

#!/bin/ash

SH_IVTOOL=/mnt/ext1/system/bin/sh_ivtool.app

STATUS="`cat /mnt/ext1/system/config/global.cfg | grep Gamma`"

ANSWER=`$SH_IVTOOL -q "$STATUS

Change gamma settings for 
Adobe or DjVu reader?"`

if [ $? -eq 0 -a "$ANSWER" == "y" ]; then

	BACKUP=`$SH_IVTOOL -q "Make a backup of global.cfg in the same place?"`
	
	if [ $? -eq 0 -a "$BACKUP" == "y" ]; then
	
	cp /mnt/ext1/system/config/global.cfg /mnt/ext1/system/config/global.cfg.old
	
	fi

		PRG=`$SH_IVTOOL -o Adobe DjVu`

		CHANGE="`echo "$STATUS" | grep "$PRG"`"

		NEW=`$SH_IVTOOL -t "$CHANGE (new x.x)"`


# here would be nice to test that NEW is grather than 0
#if [[ $NEW > 0 ]]; then
#$SH_IVTOOL -s "MAGGIORE DI ZERO"
#fi
	
		if [ $? -eq 0 -a "$PRG" == "Adobe" ]; then
	
		sed -i "s/GammaLevelAdobe=.*/GammaLevelAdobe="$NEW"/" /mnt/ext1/system/config/global.cfg

		fi

		if [ $? -eq 0 -a "$PRG" == "DjVu" ]; then

		sed -i "s/GammaLevelDjVu=.*/GammaLevelDjVu="$NEW"/" /mnt/ext1/system/config/global.cfg	
	
		fi

		$SH_IVTOOL -s "New gamma settings:
`cat /mnt/ext1/system/config/global.cfg | grep Gamma`"

fi

exit

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edit: note: added bulletproof suggestions ( $? -eq 0 -a ) in the if tests
___

could anyone help me in testing whether $NEW is greather than 0 ?

thanks

paolo