bsed man page
NAME
bsed - binary stream editor
SYNOPSIS
bsed [-vsw] [-m [min-]max] search=replace infile outfile
bsed [-vsw] [-m [min-]max] search infile
DESCRIPTION
bsed searches for a binary string in a file. If a replace
string is given, bsed copies infile to outfile, replacing
all instances of the search string with the replace string.
If infile is '-', input is from standard input; if outfile
is '-', output is to standard output.
Both the search and the replace strings can contain a combi-
nation of ascii characters and hex numbers. The following is
the algorithm used: If the string begins with a digit (0-
9), assume a hex number is beginning. Continue converting
hex digits (0-f) into binary until a non-hex digit begins,
unless the string began with "0x" or "0x": in that case just
throw away the 0x. Every 2 hex digits makes a byte; if
there is an odd number then the last digit is taken as the
low nibble of a byte. Anytime a backslash () is encoun-
tered, consider it to be a break in the conversion process
and treat it as if starting a new string. If another
backslash is immediately following it, insert a backslash.
Once converting an ascii string, continue converting it
until a backslash or end of string.
NOTE: be sure to escape the backslash from the shell.
OPTIONS
-v verbose option. First lists the search (and replace)
string in a hex-ascii dump format: each byte is listed
first in hex, followed by the ascii for each printable
character or "." for each non-printing character. Next
it gives a hex-ascii dump of the context of each match
of the search string, with the position of the match
into the file (in hex) in the middle of the dump. Out-
put is to stderr.
-s Normally bsed will list the number of matches to
stderr. This option suppresses that.
-w Normally bsed will warn if the search and replace
strings are not the same length. This option
suppresses that warning.
-m [min-]max
Normally bsed will find all the matches of the search
string. This option specifies a range of match numbers
to use. The default mininimum is number 1. Both min
and max are in decimal.
EXAMPLES
bsed -v "ab\0xa" testfile
bsed -sw "data\0=fonts\0" testfile - | od -cx
bsed -v -m5-5 "012345=0xa\bc" testfile testout