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Commands tagged xxd from sorted by
Terminal - Commands tagged xxd - 5 results
macdst="5873b856445f";macsrc="d2a791e1715a";pkt="d4c3b2a1020004000000000000000000ffff000001000000e3eab353fa1f 0b007400000074000000$macdst $macsrc 0842ffffffffffff";for i in {1..16}; do pkt="$pkt $macdst"; done; echo "$pkt" | xxd -r -p > magicpacket.pcap
2014-07-02 17:37:44
Functions: echo
0

just set macdst to the mac address of the system

you wish to wake up, the macsrc is optional but helps

use tcpreplay to broadcast or wireshark to view

end_w_nl() { [[ $(tail -c1 $1 | xxd -ps) == 0a ]] }
2012-09-18 20:11:29
User: xro
Functions: tail
Tags: tail xxd zsh
0
end_w_nl filename

will check if the last byte of filename is a unix newline character. tail -c1 yields the file's last byte and xxd converts it to hex format.

xxd <file>
2011-09-09 21:52:30
User: putnamhill
0

xxd can convert a hexdump back to binary using the -r option which can be useful for patching or editing binary files.

openssl rand -hex 6 | sed 's/\(..\)/\1:/g; s/.$//'
2010-09-23 02:31:12
User: putnamhill
Functions: sed
Tags: sed xxd openssl
14

Use the following variation for FreeBSD:

openssl rand 6 | xxd -p | sed 's/\(..\)/\1:/g; s/:$//'
echo -n $HEXBYTES | xxd -r -p | dd of=$FILE seek=$((0x$OFFSET)) bs=1 conv=notrunc
2009-03-11 17:02:24
User: zombiedeity
Functions: dd echo
2

Replace (as opposed to insert) hex opcodes, data, breakpoints, etc. without opening a hex editor.

HEXBYTES contains the hex you want to inject in ascii form (e.g. 31c0)

OFFSET is the hex offset (e.g. 49cf) into the binary FILE