Purpose: Demonstrate the use of the [binary] and [fconfigure] commands to process a binary file.
The following useful Tcl script produces a hex/ASCII dump of a binary file whose name is specified on the command line.
package require Tcl 8.3
#----------------------------------------------------------------------
#
# dumpFile --
#
# Produce a hex/ASCII dump of a file.
#
# Parameters:
# fileName -- Path name of the file
# channel -- (Optional) Channel on which to produce the dump.
# Default is stdout.
#
# Results:
# None.
#
# Side effects:
# The file is opened, dumped to the specified channel, and
# closed again.
#
#----------------------------------------------------------------------
proc dumpFile { fileName { channel stdout } } {
# Open the file, and set up to process it in binary mode.
set f [open $fileName r]
fconfigure $f \
-translation binary \
-encoding binary \
-buffering full -buffersize 16384
while { 1 } {
# Record the seek address. Read 16 bytes from the file.
set addr [tell $f]
set s [read $f 16]
# Convert the data to hex and to characters.
binary scan $s H*@0a* hex ascii
# Replace non-printing characters in the data.
regsub -all {[^[:graph:] ]} $ascii {.} ascii
# Split the 16 bytes into two 8-byte chunks
set hex1 [string range $hex 0 15]
set hex2 [string range $hex 16 31]
set ascii1 [string range $ascii 0 7]
set ascii2 [string range $ascii 8 16]
# Convert the hex to pairs of hex digits
regsub -all {..} $hex1 {& } hex1
regsub -all {..} $hex2 {& } hex2
# Put the hex and Latin-1 data to the channel
puts $channel [format {%08x %-24s %-24s %-8s %-8s} \
$addr $hex1 $hex2 $ascii1 $ascii2]
# Stop if we've reached end of file
if { [string length $s] == 0 } {
break
}
}
# When we're done, close the file.
close $f
return
}
#----------------------------------------------------------------------
#
# Main program
#
#----------------------------------------------------------------------
if { [info exists argv0] && [string equal $argv0 [info script]] } {
foreach file $argv {
puts "$file:"
dumpFile $file
}
}A slightly different version, derived from the above (not better, just a tiny bit different):
proc hexdump { filename { channel stdout } } {
# This is derived from the Tcler's WIKI, page 1599,
# original author unknown.
if { [ catch {
# Open the file, and set up to process it in binary mode.
set fid [open $filename r]
fconfigure $fid -translation binary -encoding binary
while { ! [ eof $fid ] } {
# Record the seek address. Read 16 bytes from the file.
set addr [ tell $fid ]
set s [read $fid 16]
# Convert the data to hex and to characters.
binary scan $s H*@0a* hex ascii
# Replace non-printing characters in the data.
regsub -all {[^[:graph:] ]} $ascii {.} ascii
# Split the 16 bytes into two 8-byte chunks
regexp {(.{16})(.{0,16})} $hex -> hex1 hex2
# Convert the hex to pairs of hex digits
regsub -all {..} $hex1 {& } hex1
regsub -all {..} $hex2 {& } hex2
# Put the hex and Latin-1 data to the channel
puts $channel [ format {%08x %-24s %-24s %-16s} \
$addr $hex1 $hex2 $ascii ]
}
} err ] } {
catch { ::close $fid }
return -code error $err
}
# When we're done, close the file.
catch { ::close $fid }
return
}Hmm. What version of TCL was this written for? I'm currently using 8.0, and it doesn't know anything about "string equal", or the "-encoding" option to fconfigure (which option Working with binary data says is unnecessary, anyway.) Other than that, and the fact that my regsub doesn't know anything about [:graph:], I like this program... -EE
The above code is written for Tcl 8.3.x .
The bug features^Wfixes and added features of the 8.3 series is well worth the upgrade.
TclKit appears to build in a copy of hexdump, as above.
JCW - Not any longer as of May 2002 (I've been simplifying TclKit) ... the code has been moved to CritLib, see CriTcl.