Shell Programming and Scripting

000d530: 0000 0000 0000 0000 0000 0000 493a 004f  ............I:.O
000d540: 6374 2032 3820 3230 3135 2031 393a 3234  ct 28 2015 19:24

xxd  file | sed '/493a/d' | xxd -r -p

xxd  file | awk '{
    # Only fields 2 thru 9 are the hex values we need to check.
    for(Idx=2;Idx<=9;++Idx){
        # Look for the problem data.
        if($Idx=="493a"){
            # Note stop location, so we can pad the rest of the line for xxd.
            Stop=Idx
            # Split off the portion before the problem data into an array, what we want will be in the first element.
            split($0,PartLine," 493a ")
            # Continue from where we left off and pad the line out with 0000
            for(Jdx=Stop;Jdx<=9;++Jdx){
                RemLine=RemLine " 0000"
            }
            # Output the portion before the problem data as well as the pad data.
            print PartLine[1]RemLine
            # Stop processing the file here.
            exit
        }
    }
    # Output any non-applicable lines
    print
}' | xxd -r -p

#¡/bin/bash
# bin_edit
# Create a working binary file...
echo ""
BIN_ARRAY=( 00 00 00 00 00 00 00 00 00 00 00 00 49 3a 00 4f 63 74 20 32 38 20 32 30 31 35 20 31 39 3a 32 34 )
for n in {0..31} 
do
	echo -en "\x${BIN_ARRAY[$n]}"
done > /tmp/bin
# Prove binary exists...
xxd /tmp/bin
# Now create the edit...
HEX=( $( xxd -cols 1 -p /tmp/bin ) )
# Now edit...
NEWHEX=""
for n in $( seq 0 2 ${#HEX[@]} )
do
	OLDHEX="${HEX[$n]}${HEX[$(($n+1))]}"
	if [ "$OLDHEX" = "493a" ]
	then
		:
	else
		echo -en "$NEWHEX$OLDHEX"
	fi
done > /tmp/texthexdump
echo ""
# 0x493a now removed creating new binary file...
read -r line < /tmp/texthexdump
n=0
while [ $n -lt ${#line} ]
do
	echo -en "\x${line:$n:2}"
	n=$(($n+2))
done > /tmp/newbin
xxd /tmp/newbin
echo ""

Last login: Fri Feb  5 22:34:02 on ttys000
AMIGA:barrywalker~> cd Desktop/Code/Shell
AMIGA:barrywalker~/Desktop/Code/Shell> ./bin_edit

0000000: 0000 0000 0000 0000 0000 0000 493a 004f  ............I:.O
0000010: 6374 2032 3820 3230 3135 2031 393a 3234  ct 28 2015 19:24

0000000: 0000 0000 0000 0000 0000 0000 004f 6374  .............Oct
0000010: 2032 3820 3230 3135 2031 393a 3234        28 2015 19:24

AMIGA:barrywalker~/Desktop/Code/Shell> _