% set hex 3A 3A % scan $hex %x decimal 1 % set decimal 58
MJL: [[expr] is slower but doesn't ignore invalid hexadecimal characters
% set decimal [expr 0x$hex] 58 % set hex 3G 3G % set decimal [expr 0x$hex] syntax error in expression "0x3G": extra tokens at end of expression
For extracting "unsigned" floating-point values from very long (>32 bits) integers in hex, MS has this recommendation on c.l.t.:
proc hex2dec {largeHex} {
set res 0
foreach hexDigit [split $largeHex {}] {
set new 0x$hexDigit
set res [expr {16*$res + $new}]
}
return $res
}format %X $decimalNumber
For numbers of arbitrary size, use the ll size modifer:
format %4.4llX $decimalNumber
An example in combination with a minimal field width, zero-padded:
format %04X $decimalNumber
This works for all sorts of numbers, such as
format %08.3f [expr {4*atan(1)}] ;# -> 0003.142format %4.4X [scan $c %c]
Notice that [scan $c %c] only does what one wants with newer Tcl's, those since version 8.3.0+.
Since Tcl 8.6 there's binary decode/encode hex. Example:
% binary encode hex "Hello, world!" 48656c6c6f2c20776f726c6421 % binary decode hex 42657761726520756e69636f6465206368617273 Beware unicode chars
Be careful thought, chars with code>255, only the lower byte is encoded. And at decoding time each pair of hex digits XY will be encoded into unicode char U+00XY. If you need utf-8 hex conversion, use:
% binary encode hex [encoding convertto utf-8 "€"] e282ac % encoding convertfrom utf-8 [binary decode hex e282ac] €
mfi: Can someone suggest a pure Tcl replacement for xxd UNIX command (creates a hex dump of a given string)?
RS: Sure enough:
proc string2hex {string} {
set where 0
set res {}
while {$where<[string length $string]} {
set str [string range $string $where [expr $where+15]]
if {![binary scan $str H* t] || $t==""} break
regsub -all (....) $t {\1 } t4
regsub -all (..) $t {\1 } t2
set asc ""
foreach i $t2 {
scan $i %2x c
append asc [expr {$c>=32 && $c<=127? [format %c $c]: "."}]
}
lappend res [format "%7.7x: %-42s %s" $where $t4 $asc]
incr where 16
}
join $res \n
}See also Dump a file in hex and ASCII
LH: Here's something similar, but speeds things up by using external storage for a character map that is generated one time:
proc xxd2 {charMapname convertString} {
upvar $charMapname mycharMap
#generate a character map for displaying hex equiv of chars [0..127]
if { 0 == [string length $mycharMap] } {
# init charmap
for {set i 0 } { $i < 128 } { incr i } {
append mycharMap "[format " \\%03o {%02x }" $i $i ]"
}
}
string map $mycharMap $convertString
}
#example:
set hexcharMap "" ;# global variable
xxd2 hexcharMap "abcdz" ;# slow, even if initialized
string map $hexcharMap "abcdez" ;# much fasterBob Rashkin: I know there are plenty of these around but I wanted something to do a hex analysis without all the overhead of editing:
proc getFile {} {
#this is just a file search before the new tk_getOpenFile
global dirlst dirname filelst flnm
set dirname [pwd]
set filelst [glob -directory $dirname *]
lappend filelst "$dirname/.."
toplevel .open
frame .open.up -borderwidth 4
frame .open.bottom -borderwidth 4
pack .open.up .open.bottom -side top
set w .open.up
listbox $w.hval -height 8 -font {courier 9} -exportselection 1 \
-yscrollcommand "$w.yscr set" -listvar filelst \
-xscrollcommand "$w.xscr set" -width 55
scrollbar $w.yscr -command "$w.hval yview"
scrollbar $w.xscr -command "$w.hval xview" -orient horizontal
pack $w.yscr -side right -fill y
pack $w.hval $w.xscr -side top -fill x
bind .open.up.hval <Double-Button-1> {
set filename [lindex $filelst [.open.up.hval curselection]]
}
bind .open.up.hval <Return> {
set filename [lindex $filelst [.open.up.hval curselection]]
}
set u .open.bottom
entry $u.filen -textvariable filename -width 50
button $u.opn -text Open -command {
if [file isdirectory $filename] {
set filelst [glob -directory $filename *]
lappend filelst "$filename/.."
} else {
destroy .open
set flnm $filename
}
}
pack $u.filen $u.opn -side left -padx 8
bind .open.bottom.filen <Return> {
if [file isdirectory $filename] {
set filelst [glob -directory $filename *]
} else {
destroy .open
set flnm $filename
}
}
focus .open.bottom.filen
}
proc closeUp {fid} {
close $fid
.top.val delete 0.0 end
}
proc doScan {stadd fsz} {
global fid fid2 val hval flnm tag
#
. configure -cursor watch
update
#
set bold "-background #44aaaa -foreground white"
set normal "-background {} -foreground {}"
.top.val delete 0.0 end
if {$fsz == 0} {set fsz [expr {[file size $flnm] -$stadd}]}
#.top.val insert end "Scanning $fsz bytes\n"
if {$fsz>5000} {
.top.val insert end "scanning more than 5000 bytes at a time\n" c1
.top.val insert end "can result in unpredictable behavior\n" c1
}
set nlns [expr {$fsz/16}]
if {[expr {fmod($fsz,16)}]>0} {incr nlns}
set fid2 [open $flnm r]
fconfigure $fid2 -translation binary;#<<<<<<<---this is the key statement!
seek $fid2 $stadd start
cd [file dirname $flnm]
set t 0
set lnadd $stadd
for {set ln 1} {$ln <= $nlns} {incr ln} {
set val [read $fid2 16]
set nbyt [string length $val]
set fmnum [expr {2*$nbyt}]
binary scan $val H$fmnum hval;#<<<<<<<<<<<<<<<<<convert to hex
.top.val insert end "[format %5d $lnadd]: "
.top.val insert end $hval d$t
set val [string map {"\t" " " "\n" " "} $val]
set astr " "
set spcs [expr {32-$fmnum}]
for {set i 1} {$i<=$spcs} {incr i} {append astr " "}
append astr " $val"
.top.val insert end $astr
.top.val insert end \n
lappend dlist d$t
incr t
incr lnadd 16
if [eof $fid2] {set ln $nlns}
}
close $fid2
.top.val tag configure c1 -foreground red
# Create bindings for tags.
foreach tag $dlist {
.top.val tag bind $tag <Any-Enter> ".top.val tag configure $tag $bold"
.top.val tag bind $tag <Any-Leave> ".top.val tag configure $tag $normal"
.top.val tag bind $tag <1> "scanBin $tag"
}
#
. configure -cursor arrow
update -cursor arrow
#
}
proc scanBin {hxline} {
global val val1 val2 val3
.middle.left.hval delete 0.0 end
.middle.right.hval delete 0.0 end
set val [.top.val get $hxline.first $hxline.last]
set val2 [binary format "H32" $val]
for {set i 0} {$i<=7} {incr i} {
set val3 [string range $val2 $i $i]
binary scan $val3 B8 hval;#<<<
binary scan $val3 H2 val4
binary scan $val3 c dval
set dval [expr {( $dval + 0x100 ) % 0x100}]
.middle.left.hval insert end $val4\t$hval\t$dval\n
}
for {set i 8} {$i<=15} {incr i} {
set val3 [string range $val2 $i $i]
binary scan $val3 B8 hval;#<<<
binary scan $val3 H2 val4
binary scan $val3 c dval
set dval [expr {( $dval + 0x100 ) % 0x100}]
.middle.right.hval insert end $val4\t$hval\t$dval\n
}
}
wm title . Binary_Data_Analyzer
wm deiconify .
frame .top -borderwidth 4
frame .middle -borderwidth 4
frame .bottom -borderwidth 4
pack .top .middle .bottom -side top
set w .top
for {set i 0} {$i<65} {incr i} {append lblstr " "}
set lblstr [string replace $lblstr 2 5 Addr]
set lblstr [string replace $lblstr 15 26 "16 Bytes HEX"]
set lblstr [string replace $lblstr 52 56 ASCII]
label $w.read2 -text $lblstr -fg blue -font {courier 9}
text $w.val -height 12 -width 65 -yscrollcommand "$w.yscr set" -font {courier 9}
scrollbar $w.yscr -command "$w.val yview"
pack $w.yscr -side right -fill y
pack $w.read2 $w.val -side top
set w .middle
frame .middle.left -borderwidth 4
frame .middle.right -borderwidth 4
pack .middle.left .middle.right -side left
set w .middle.left
for {set i 1} {$i<=28} {incr i} {append binlbl " "}
set binlbl [string replace $binlbl 0 2 Hex]
set binlbl [string replace $binlbl 9 14 Binary]
set binlbl [string replace $binlbl 21 28 Decimal]
label $w.scan -text "BinaryScan 0-7"
label $w.tit2 -text $binlbl -font {courier 9} -fg blue
text $w.hval -height 8 -width 28 -font {courier 9}
pack $w.scan $w.tit2 $w.hval -side top
set w .middle.right
label $w.scan -text "BinaryScan 8-15"
label $w.tit2 -text $binlbl -font {courier 9} -fg blue
text $w.hval -height 8 -width 28 -font {courier 9}
pack $w.scan $w.tit2 $w.hval -side top
if {[winfo depth $w] > 1} {
set bold "-background #43ce80 -relief raised -borderwidth 1"
set normal "-background {} -relief flat"
} else {
set bold "-foreground white -background black"
set normal "-foreground {} -background {}"
}
set w .bottom
label $w.flbl -text "File name: "
entry $w.fent -textvariable flnm -width 42 -font {-size 9 -weight bold}
button $w.scan -text Scan -width 42 -activebackground white -command {doScan $stadd $lngt}
button $w.getf -text File -command {getFile}
frame $w.add -borderwidth 4
pack $w.add -side bottom
pack $w.scan -side bottom
pack $w.flbl $w.fent $w.getf -side left -padx 6
set stadd 0
set lngt 0
if {$argc>0} {set flnm [lindex $argv 0];set lngt 5000;doScan 0 5000}
set w .bottom.add
label $w.stlab -text "start address:"
entry $w.stent -textvariable stadd -width 8
label $w.lnlab -text Length:
entry $w.lnent -textvariable lngt -width 8
label $w.wrng -text "0=to EOF" -justify left
pack $w.stlab $w.stent $w.lnlab $w.lnent $w.wrng -side left -padx 6
bind . <Escape> exit
bind . <Return> {doScan $stadd $lngt}
bind .bottom.add.lnent <Button-3> {set lngt [file size $flnm]}
menu .menu -tearoff 0
set m .menu.help
menu $m -tearoff 0
.menu add cascade -label "Don't panic" -menu $m -underline 0
$m add cascade -label "System" -menu .menu.help.sys -underline 0
$m add cascade -label "General" -menu .menu.help.gen -underline 0
$m add cascade -label "Quirks" -menu .menu.help.qks -underline 0
set m .menu.help.gen
menu $m -tearoff 0
$m add check -label "Scan button reads in file as HEX and ASCII in 16byte chunks"
$m add check -label "If start is not 0, reading starts at the address specified (in decimal)"
$m add check -label "If Length is 0, the entire file is read (or to EOF)"
$m add check -label "Otherwise only (decimal) Length number of bytes is read"
$m add separator
$m add check -label "If invoked from the command line, will take filename as argument"
$m add check -label " and scan from 0 to 5000"
$m add separator
$m add check -label "Move cursor over any line of HEX,"
$m add check -label "Left click to analyze each byte of highlit line"
$m add separator
$m add check -label "The File button opens a listbox to search files"
$m add check -label "Click Open to return the file to the main window file entry"
$m add check -label " or open the indicated directory"
set m .menu.help.sys
menu $m -tearoff 0
$m add check -label "Requires Tcl/Tk 8.3 or higher"
set m .menu.help.qks
menu $m -tearoff 0
$m add check -label "Right click in the Length entry to compute file size"
$m add check -label "Very big files can overflow something (tag array?)"
$m add check -label ">Not sure what 'very big' is but 5000 bytes or"
$m add check -label " fewer at a time certainly works"
$m add check -label "<Enter> (return) anywhere in the main window is the same as Scan"
$m add separator
$m add check -label "<Enter> in the File window listbox brings the selection"
$m add check -label " to the entry box"
$m add check -label "<Enter> in the file entry in the File window is the same as Open"
. configure -menu .menuAfter that much code, here's a little one: convert a string to hex, so the result can be reparsed as the original string:
proc string2hex s {
binary scan $s H* hex
regsub -all (..) $hex {\\x\1}
} ;# RS% string2hex "hello, world!" \x68\x65\x6c\x6c\x6f\x2c\x20\x77\x6f\x72\x6c\x64\x21 % subst [string2hex "hello, world!"] hello, world!
George Petasis: According to Donal Fellows, "encoding convertto utf-8" may be required before `[[binary scan] is called on the string, as the internal representation of Tcl may not be "exactly" utf-8, thus a proper utf-8 representation must be generated first. Something like:
proc string2hex s {
binary scan [encoding convertto utf-8 $s] H* hex
regsub -all (..) $hex {\\x\1}
} ;# RSAM: I needed to inspect the actual value of a number in a binary file. Actually the number was repeated many times, it represented a "missing value". Of course the program that needed to read this file had a different idea about what value constitutes a missing value. So I wanted to know what the actual value was (in human terms).
Via a hex viewer, I could see that the bytes were "5c ff 79 c4". In the chatroom, dkf came up with the following solution:
binary scan [binary format I 0x5cff79c4] f xx set xx -999.989990234
Explanation:
A poster on comp.lang.tcl asked how to convert binary to hex[L1 ]. One proc that was provided in reply was:
proc bin2hex {bin} {
set result ""
set prepend [string repeat 0 [expr (4-[string length $bin]%4)%4]]
foreach g [regexp -all -inline {[01]{4}} $prepend$bin] {
foreach {b3 b2 b1 b0} [split $g ""] {
append result [format %X [expr {$b3*8+$b2*4+$b1*2+$b0}]]
}
}
return $result
} Another, by dkf was:
proc bin2hex {bin} {
set result ""
set prepend [string repeat 0 [expr (4-[string length $bin]%4)%4]]
foreach g [regexp -all -inline {[01]{4}} $prepend$bin] {
foreach {b3 b2 b1 b0} [split $g ""] {
append result [format %X [expr {$b3*8+$b2*4+$b1*2+$b0}]]
}
}
return $result
} And another replier pointed to [L2 ], another thread from a couple weeks earlier, which generated:
proc convBinToHexNib { binIn {mode hex} } {
set ret error
switch -glob -- $mode {
hex* {
set val [binary format B $binIn]
binary scan H $val ret
} dec* {
set val [binary format B* 0000$binIn ]
binary scan $val c ret
} default {
puts stderr "WHAT mode? $mode"
}
}
return $ret
}and
# This works for up to 32 bits.
# Any more and the value will roll over.
proc bin2int {binstring} {
set ret 0
foreach bit [split $binstring ""] {
set ret [expr {$ret << 1}]
if {[string is boolean $bit]} {
set ret [expr {$ret | $bit}]
} else {
error "string is not binary!"
}
}
return $ret
}
# Usage: convert nybble to decimal:
set dec [bin2int 1010]
# convert nybble to hex:
format %x [bin2int 1010]and
proc convBinToHexNib {binIn mode} {
binary scan [binary format B8 0000$binIn] c1 num
switch -exact -- $mode {
dec {
set result $num
}
hex {
set result [format %x $num]
}
default {
error "Unknown mode '$mode'"
}
}
return $result
} as possible solutions.