How to create a hex dump of file containing only the hex characters without spaces in bash?
Format strings can make hexdump behave exactly as you want it to (no whitespace at all, byte by byte):
hexdump -ve '1/1 "%.2x"'1/1 means "each format is applied once and takes one byte", and "%.2x" is the actual format string, like in printf. In this case: 2-character hexadecimal number, leading zeros if shorter.