updated for version 7.1a

This commit is contained in:
Bram Moolenaar
2007-05-05 18:27:07 +00:00
parent c81e5e79a0
commit 83e138c606
10 changed files with 347 additions and 945 deletions

View File

@ -86,13 +86,12 @@ OPTIONS
found in hexdump.
-s [+][-]seek
start at <seek> bytes abs. (or rel.) infile offset. + fRindi-
cates that the seek is relative to the current stdin file posi-
tion (meaningless when not reading from stdin). - indicates
that the seek should be that many characters from the end of the
input (or if combined with +: before the current stdin file
position). Without -s option, xxd starts at the current file
position.
start at <seek> bytes abs. (or rel.) infile offset. + indicates
that the seek is relative to the current stdin file position
(meaningless when not reading from stdin). - indicates that the
seek should be that many characters from the end of the input
(or if combined with +: before the current stdin file position).
Without -s option, xxd starts at the current file position.
-u use upper case hex letters. Default is lower case.
@ -101,20 +100,20 @@ OPTIONS
CAVEATS
xxd -r has some builtin magic while evaluating line number information.
If the output file is seekable, then the linenumbers at the start of
each hexdump line may be out of order, lines may be missing, or over-
lapping. In these cases xxd will lseek(2) to the next position. If the
output file is not seekable, only gaps are allowed, which will be
If the output file is seekable, then the linenumbers at the start of
each hexdump line may be out of order, lines may be missing, or over-
lapping. In these cases xxd will lseek(2) to the next position. If the
output file is not seekable, only gaps are allowed, which will be
filled by null-bytes.
xxd -r never generates parse errors. Garbage is silently skipped.
When editing hexdumps, please note that xxd -r skips everything on the
When editing hexdumps, please note that xxd -r skips everything on the
input line after reading enough columns of hexadecimal data (see option
-c). This also means, that changes to the printable ascii (or ebcdic)
columns are always ignored. Reverting a plain (or postscript) style
hexdump with xxd -r -p does not depend on the correct number of col-
umns. Here anything that looks like a pair of hex-digits is inter-
-c). This also means, that changes to the printable ascii (or ebcdic)
columns are always ignored. Reverting a plain (or postscript) style
hexdump with xxd -r -p does not depend on the correct number of col-
umns. Here anything that looks like a pair of hex-digits is inter-
preted.
Note the difference between
@ -122,28 +121,28 @@ CAVEATS
and
% xxd -i < file
xxd -s +seek may be different from xxd -s seek, as lseek(2) is used to
xxd -s +seek may be different from xxd -s seek, as lseek(2) is used to
"rewind" input. A '+' makes a difference if the input source is stdin,
and if stdin's file position is not at the start of the file by the
time xxd is started and given its input. The following examples may
and if stdin's file position is not at the start of the file by the
time xxd is started and given its input. The following examples may
help to clarify (or further confuse!)...
Rewind stdin before reading; needed because the `cat' has already read
Rewind stdin before reading; needed because the `cat' has already read
to the end of stdin.
% sh -c "cat > plain_copy; xxd -s 0 > hex_copy" < file
Hexdump from file position 0x480 (=1024+128) onwards. The `+' sign
Hexdump from file position 0x480 (=1024+128) onwards. The `+' sign
means "relative to the current position", thus the `128' adds to the 1k
where dd left off.
% sh -c "dd of=plain_snippet bs=1k count=1; xxd -s +128 > hex_snippet"
% sh -c "dd of=plain_snippet bs=1k count=1; xxd -s +128 > hex_snippet"
< file
Hexdump from file position 0x100 ( = 1024-768) on.
% sh -c "dd of=plain_snippet bs=1k count=1; xxd -s +-768 > hex_snippet"
< file
However, this is a rare situation and the use of `+' is rarely needed.
The author prefers to monitor the effect of xxd with strace(1) or
However, this is a rare situation and the use of `+' is rarely needed.
The author prefers to monitor the effect of xxd with strace(1) or
truss(1), whenever -s is used.
EXAMPLES
@ -153,7 +152,7 @@ EXAMPLES
Print 3 lines (hex 0x30 bytes) from the end of file.
% xxd -s -0x30 file
Print 120 bytes as continuous hexdump with 40 octets per line.
Print 120 bytes as continuous hexdump with 20 octets per line.
% xxd -l 120 -ps -c 20 xxd.1
2e54482058584420312022417567757374203139
39362220224d616e75616c207061676520666f72
@ -187,7 +186,7 @@ EXAMPLES
% xxd -s 0x36 -l 13 -c 13 xxd.1
0000036: 3235 7468 204d 6179 2031 3939 36 25th May 1996
Create a 65537 byte file with all bytes 0x00, except for the last one
Create a 65537 byte file with all bytes 0x00, except for the last one
which is 'A' (hex 0x41).
% echo "010000: 41" | xxd -r > file
@ -197,7 +196,7 @@ EXAMPLES
*
000fffc: 0000 0000 40 ....A
Create a 1 byte file containing a single 'A' character. The number
Create a 1 byte file containing a single 'A' character. The number
after '-r -s' adds to the linenumbers found in the file; in effect, the
leading bytes are suppressed.
% echo "010000: 41" | xxd -r -s -0x10000 > file
@ -239,7 +238,7 @@ SEE ALSO
uuencode(1), uudecode(1), patch(1)
WARNINGS
The tools weirdness matches its creators brain. Use entirely at your
The tools weirdness matches its creators brain. Use entirely at your
own risk. Copy files. Trace it. Become a wizard.
VERSION