Oops, forgot to svn add this
This commit is contained in:
Erik van der Kouwe
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47
man/man1/bzdiff.1
Normal file
47
man/man1/bzdiff.1
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\"Shamelessly copied from zmore.1 by Philippe Troin <phil@fifi.org>
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\"for Debian GNU/Linux
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.TH BZDIFF 1
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.SH NAME
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bzcmp, bzdiff \- compare bzip2 compressed files
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.SH SYNOPSIS
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.B bzcmp
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[ cmp_options ] file1
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[ file2 ]
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.br
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.B bzdiff
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[ diff_options ] file1
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[ file2 ]
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.SH DESCRIPTION
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.I Bzcmp
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and
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.I bzdiff
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are used to invoke the
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.I cmp
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or the
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.I diff
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program on bzip2 compressed files. All options specified are passed
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directly to
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.I cmp
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or
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.IR diff "."
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If only 1 file is specified, then the files compared are
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.I file1
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and an uncompressed
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.IR file1 ".bz2."
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If two files are specified, then they are uncompressed if necessary and fed to
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.I cmp
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or
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.IR diff "."
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The exit status from
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.I cmp
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or
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.I diff
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is preserved.
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.SH "SEE ALSO"
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cmp(1), diff(1), bzmore(1), bzless(1), bzgrep(1), bzip2(1)
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.SH BUGS
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|
Messages from the
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.I cmp
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or
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.I diff
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programs refer to temporary filenames instead of those specified.
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56
man/man1/bzgrep.1
Normal file
56
man/man1/bzgrep.1
Normal file
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\"Shamelessly copied from zmore.1 by Philippe Troin <phil@fifi.org>
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\"for Debian GNU/Linux
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.TH BZGREP 1
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.SH NAME
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bzgrep, bzfgrep, bzegrep \- search possibly bzip2 compressed files for a regular expression
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.SH SYNOPSIS
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.B bzgrep
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[ grep_options ]
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.BI [\ -e\ ] " pattern"
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.IR filename ".\|.\|."
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.br
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.B bzegrep
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[ egrep_options ]
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.BI [\ -e\ ] " pattern"
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.IR filename ".\|.\|."
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.br
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.B bzfgrep
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[ fgrep_options ]
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.BI [\ -e\ ] " pattern"
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.IR filename ".\|.\|."
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.SH DESCRIPTION
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.IR Bzgrep
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|
is used to invoke the
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|
.I grep
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|
on bzip2-compressed files. All options specified are passed directly to
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.I grep.
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If no file is specified, then the standard input is decompressed
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|
if necessary and fed to grep.
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Otherwise the given files are uncompressed if necessary and fed to
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.I grep.
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.PP
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If
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.I bzgrep
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is invoked as
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.I bzegrep
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or
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.I bzfgrep
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|
then
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.I egrep
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or
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.I fgrep
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|
is used instead of
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.I grep.
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If the GREP environment variable is set,
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.I bzgrep
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|
uses it as the
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.I grep
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program to be invoked. For example:
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|
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for sh: GREP=fgrep bzgrep string files
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for csh: (setenv GREP fgrep; bzgrep string files)
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.SH AUTHOR
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Charles Levert (charles@comm.polymtl.ca). Adapted to bzip2 by Philippe
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Troin <phil@fifi.org> for Debian GNU/Linux.
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.SH "SEE ALSO"
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grep(1), egrep(1), fgrep(1), bzdiff(1), bzmore(1), bzless(1), bzip2(1)
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454
man/man1/bzip2.1
Normal file
454
man/man1/bzip2.1
Normal file
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.PU
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.TH bzip2 1
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.SH NAME
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bzip2, bunzip2 \- a block-sorting file compressor, v1.0.3
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.br
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bzcat \- decompresses files to stdout
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.br
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bzip2recover \- recovers data from damaged bzip2 files
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.SH SYNOPSIS
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.ll +8
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.B bzip2
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.RB [ " \-cdfkqstvzVL123456789 " ]
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[
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.I "filenames \&..."
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]
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.ll -8
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.br
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.B bunzip2
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.RB [ " \-fkvsVL " ]
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[
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.I "filenames \&..."
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]
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.br
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.B bzcat
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.RB [ " \-s " ]
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[
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.I "filenames \&..."
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]
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.br
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.B bzip2recover
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.I "filename"
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.SH DESCRIPTION
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|
.I bzip2
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|
compresses files using the Burrows-Wheeler block sorting
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|
text compression algorithm, and Huffman coding. Compression is
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|
generally considerably better than that achieved by more conventional
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LZ77/LZ78-based compressors, and approaches the performance of the PPM
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|
family of statistical compressors.
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The command-line options are deliberately very similar to
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|
those of
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.I GNU gzip,
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|
but they are not identical.
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|
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|
.I bzip2
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|
expects a list of file names to accompany the
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|
command-line flags. Each file is replaced by a compressed version of
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|
itself, with the name "original_name.bz2".
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|
Each compressed file
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|
has the same modification date, permissions, and, when possible,
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|
ownership as the corresponding original, so that these properties can
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|
be correctly restored at decompression time. File name handling is
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|
naive in the sense that there is no mechanism for preserving original
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|
file names, permissions, ownerships or dates in filesystems which lack
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|
these concepts, or have serious file name length restrictions, such as
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MS-DOS.
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|
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.I bzip2
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and
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.I bunzip2
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|
will by default not overwrite existing
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|
files. If you want this to happen, specify the \-f flag.
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If no file names are specified,
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.I bzip2
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|
compresses from standard
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|
input to standard output. In this case,
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.I bzip2
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|
will decline to
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|
write compressed output to a terminal, as this would be entirely
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|
incomprehensible and therefore pointless.
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|
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.I bunzip2
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|
(or
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.I bzip2 \-d)
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|
decompresses all
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|
specified files. Files which were not created by
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|
.I bzip2
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|
will be detected and ignored, and a warning issued.
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.I bzip2
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|
attempts to guess the filename for the decompressed file
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from that of the compressed file as follows:
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filename.bz2 becomes filename
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filename.bz becomes filename
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filename.tbz2 becomes filename.tar
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filename.tbz becomes filename.tar
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anyothername becomes anyothername.out
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If the file does not end in one of the recognised endings,
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.I .bz2,
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|
.I .bz,
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|
.I .tbz2
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|
or
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|
.I .tbz,
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|
.I bzip2
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|
complains that it cannot
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|
guess the name of the original file, and uses the original name
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with
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.I .out
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appended.
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As with compression, supplying no
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filenames causes decompression from
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standard input to standard output.
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.I bunzip2
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|
will correctly decompress a file which is the
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|
concatenation of two or more compressed files. The result is the
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concatenation of the corresponding uncompressed files. Integrity
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testing (\-t)
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of concatenated
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compressed files is also supported.
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You can also compress or decompress files to the standard output by
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giving the \-c flag. Multiple files may be compressed and
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decompressed like this. The resulting outputs are fed sequentially to
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stdout. Compression of multiple files
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in this manner generates a stream
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containing multiple compressed file representations. Such a stream
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can be decompressed correctly only by
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.I bzip2
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|
version 0.9.0 or
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|
later. Earlier versions of
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.I bzip2
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will stop after decompressing
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the first file in the stream.
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.I bzcat
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|
(or
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.I bzip2 -dc)
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|
decompresses all specified files to
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the standard output.
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|
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|
.I bzip2
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|
will read arguments from the environment variables
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|
.I BZIP2
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|
and
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|
.I BZIP,
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|
in that order, and will process them
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|
before any arguments read from the command line. This gives a
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|
convenient way to supply default arguments.
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Compression is always performed, even if the compressed
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file is slightly
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larger than the original. Files of less than about one hundred bytes
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tend to get larger, since the compression mechanism has a constant
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overhead in the region of 50 bytes. Random data (including the output
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of most file compressors) is coded at about 8.05 bits per byte, giving
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an expansion of around 0.5%.
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As a self-check for your protection,
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|
.I
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|
bzip2
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|
uses 32-bit CRCs to
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|
make sure that the decompressed version of a file is identical to the
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|
original. This guards against corruption of the compressed data, and
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|
against undetected bugs in
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|
.I bzip2
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|
(hopefully very unlikely). The
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|
chances of data corruption going undetected is microscopic, about one
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|
chance in four billion for each file processed. Be aware, though, that
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|
the check occurs upon decompression, so it can only tell you that
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|
something is wrong. It can't help you
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|
recover the original uncompressed
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|
data. You can use
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|
.I bzip2recover
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|
to try to recover data from
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|
damaged files.
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|
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|
Return values: 0 for a normal exit, 1 for environmental problems (file
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|
not found, invalid flags, I/O errors, &c), 2 to indicate a corrupt
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|
compressed file, 3 for an internal consistency error (eg, bug) which
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|
caused
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|
.I bzip2
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|
to panic.
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|
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|
.SH OPTIONS
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|
.TP
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|
.B \-c --stdout
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|
Compress or decompress to standard output.
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|
.TP
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|
.B \-d --decompress
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|
Force decompression.
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|
.I bzip2,
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|
.I bunzip2
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|
and
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|
.I bzcat
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|
are
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|
really the same program, and the decision about what actions to take is
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|
done on the basis of which name is used. This flag overrides that
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|
mechanism, and forces
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|
.I bzip2
|
||||||
|
to decompress.
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|
.TP
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|
.B \-z --compress
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|
The complement to \-d: forces compression, regardless of the
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|
invocation name.
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|
.TP
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|
.B \-t --test
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|
Check integrity of the specified file(s), but don't decompress them.
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|
This really performs a trial decompression and throws away the result.
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|
.TP
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|
.B \-f --force
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|
Force overwrite of output files. Normally,
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|
.I bzip2
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||||||
|
will not overwrite
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||||||
|
existing output files. Also forces
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||||||
|
.I bzip2
|
||||||
|
to break hard links
|
||||||
|
to files, which it otherwise wouldn't do.
|
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|
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||||||
|
bzip2 normally declines to decompress files which don't have the
|
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|
correct magic header bytes. If forced (-f), however, it will pass
|
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|
such files through unmodified. This is how GNU gzip behaves.
|
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|
.TP
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|
.B \-k --keep
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|
Keep (don't delete) input files during compression
|
||||||
|
or decompression.
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|
.TP
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|
.B \-s --small
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|
Reduce memory usage, for compression, decompression and testing. Files
|
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|
are decompressed and tested using a modified algorithm which only
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|
requires 2.5 bytes per block byte. This means any file can be
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|
decompressed in 2300k of memory, albeit at about half the normal speed.
|
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|
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|
During compression, \-s selects a block size of 200k, which limits
|
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|
memory use to around the same figure, at the expense of your compression
|
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|
ratio. In short, if your machine is low on memory (8 megabytes or
|
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|
less), use \-s for everything. See MEMORY MANAGEMENT below.
|
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|
.TP
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|
.B \-q --quiet
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|
Suppress non-essential warning messages. Messages pertaining to
|
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|
I/O errors and other critical events will not be suppressed.
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|
.TP
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|
.B \-v --verbose
|
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|
Verbose mode -- show the compression ratio for each file processed.
|
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|
Further \-v's increase the verbosity level, spewing out lots of
|
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|
information which is primarily of interest for diagnostic purposes.
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|
.TP
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|
.B \-L --license -V --version
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|
Display the software version, license terms and conditions.
|
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|
.TP
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|
.B \-1 (or \-\-fast) to \-9 (or \-\-best)
|
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|
Set the block size to 100 k, 200 k .. 900 k when compressing. Has no
|
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|
effect when decompressing. See MEMORY MANAGEMENT below.
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|
The \-\-fast and \-\-best aliases are primarily for GNU gzip
|
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|
compatibility. In particular, \-\-fast doesn't make things
|
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|
significantly faster.
|
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|
And \-\-best merely selects the default behaviour.
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|
.TP
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|
.B \--
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|
Treats all subsequent arguments as file names, even if they start
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|
with a dash. This is so you can handle files with names beginning
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|
with a dash, for example: bzip2 \-- \-myfilename.
|
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|
.TP
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|
.B \--repetitive-fast --repetitive-best
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|
These flags are redundant in versions 0.9.5 and above. They provided
|
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|
some coarse control over the behaviour of the sorting algorithm in
|
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|
earlier versions, which was sometimes useful. 0.9.5 and above have an
|
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|
improved algorithm which renders these flags irrelevant.
|
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|
|
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|
.SH MEMORY MANAGEMENT
|
||||||
|
.I bzip2
|
||||||
|
compresses large files in blocks. The block size affects
|
||||||
|
both the compression ratio achieved, and the amount of memory needed for
|
||||||
|
compression and decompression. The flags \-1 through \-9
|
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|
specify the block size to be 100,000 bytes through 900,000 bytes (the
|
||||||
|
default) respectively. At decompression time, the block size used for
|
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|
compression is read from the header of the compressed file, and
|
||||||
|
.I bunzip2
|
||||||
|
then allocates itself just enough memory to decompress
|
||||||
|
the file. Since block sizes are stored in compressed files, it follows
|
||||||
|
that the flags \-1 to \-9 are irrelevant to and so ignored
|
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|
during decompression.
|
||||||
|
|
||||||
|
Compression and decompression requirements,
|
||||||
|
in bytes, can be estimated as:
|
||||||
|
|
||||||
|
Compression: 400k + ( 8 x block size )
|
||||||
|
|
||||||
|
Decompression: 100k + ( 4 x block size ), or
|
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|
100k + ( 2.5 x block size )
|
||||||
|
|
||||||
|
Larger block sizes give rapidly diminishing marginal returns. Most of
|
||||||
|
the compression comes from the first two or three hundred k of block
|
||||||
|
size, a fact worth bearing in mind when using
|
||||||
|
.I bzip2
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||||||
|
on small machines.
|
||||||
|
It is also important to appreciate that the decompression memory
|
||||||
|
requirement is set at compression time by the choice of block size.
|
||||||
|
|
||||||
|
For files compressed with the default 900k block size,
|
||||||
|
.I bunzip2
|
||||||
|
will require about 3700 kbytes to decompress. To support decompression
|
||||||
|
of any file on a 4 megabyte machine,
|
||||||
|
.I bunzip2
|
||||||
|
has an option to
|
||||||
|
decompress using approximately half this amount of memory, about 2300
|
||||||
|
kbytes. Decompression speed is also halved, so you should use this
|
||||||
|
option only where necessary. The relevant flag is -s.
|
||||||
|
|
||||||
|
In general, try and use the largest block size memory constraints allow,
|
||||||
|
since that maximises the compression achieved. Compression and
|
||||||
|
decompression speed are virtually unaffected by block size.
|
||||||
|
|
||||||
|
Another significant point applies to files which fit in a single block
|
||||||
|
-- that means most files you'd encounter using a large block size. The
|
||||||
|
amount of real memory touched is proportional to the size of the file,
|
||||||
|
since the file is smaller than a block. For example, compressing a file
|
||||||
|
20,000 bytes long with the flag -9 will cause the compressor to
|
||||||
|
allocate around 7600k of memory, but only touch 400k + 20000 * 8 = 560
|
||||||
|
kbytes of it. Similarly, the decompressor will allocate 3700k but only
|
||||||
|
touch 100k + 20000 * 4 = 180 kbytes.
|
||||||
|
|
||||||
|
Here is a table which summarises the maximum memory usage for different
|
||||||
|
block sizes. Also recorded is the total compressed size for 14 files of
|
||||||
|
the Calgary Text Compression Corpus totalling 3,141,622 bytes. This
|
||||||
|
column gives some feel for how compression varies with block size.
|
||||||
|
These figures tend to understate the advantage of larger block sizes for
|
||||||
|
larger files, since the Corpus is dominated by smaller files.
|
||||||
|
|
||||||
|
Compress Decompress Decompress Corpus
|
||||||
|
Flag usage usage -s usage Size
|
||||||
|
|
||||||
|
-1 1200k 500k 350k 914704
|
||||||
|
-2 2000k 900k 600k 877703
|
||||||
|
-3 2800k 1300k 850k 860338
|
||||||
|
-4 3600k 1700k 1100k 846899
|
||||||
|
-5 4400k 2100k 1350k 845160
|
||||||
|
-6 5200k 2500k 1600k 838626
|
||||||
|
-7 6100k 2900k 1850k 834096
|
||||||
|
-8 6800k 3300k 2100k 828642
|
||||||
|
-9 7600k 3700k 2350k 828642
|
||||||
|
|
||||||
|
.SH RECOVERING DATA FROM DAMAGED FILES
|
||||||
|
.I bzip2
|
||||||
|
compresses files in blocks, usually 900kbytes long. Each
|
||||||
|
block is handled independently. If a media or transmission error causes
|
||||||
|
a multi-block .bz2
|
||||||
|
file to become damaged, it may be possible to
|
||||||
|
recover data from the undamaged blocks in the file.
|
||||||
|
|
||||||
|
The compressed representation of each block is delimited by a 48-bit
|
||||||
|
pattern, which makes it possible to find the block boundaries with
|
||||||
|
reasonable certainty. Each block also carries its own 32-bit CRC, so
|
||||||
|
damaged blocks can be distinguished from undamaged ones.
|
||||||
|
|
||||||
|
.I bzip2recover
|
||||||
|
is a simple program whose purpose is to search for
|
||||||
|
blocks in .bz2 files, and write each block out into its own .bz2
|
||||||
|
file. You can then use
|
||||||
|
.I bzip2
|
||||||
|
\-t
|
||||||
|
to test the
|
||||||
|
integrity of the resulting files, and decompress those which are
|
||||||
|
undamaged.
|
||||||
|
|
||||||
|
.I bzip2recover
|
||||||
|
takes a single argument, the name of the damaged file,
|
||||||
|
and writes a number of files "rec00001file.bz2",
|
||||||
|
"rec00002file.bz2", etc, containing the extracted blocks.
|
||||||
|
The output filenames are designed so that the use of
|
||||||
|
wildcards in subsequent processing -- for example,
|
||||||
|
"bzip2 -dc rec*file.bz2 > recovered_data" -- processes the files in
|
||||||
|
the correct order.
|
||||||
|
|
||||||
|
.I bzip2recover
|
||||||
|
should be of most use dealing with large .bz2
|
||||||
|
files, as these will contain many blocks. It is clearly
|
||||||
|
futile to use it on damaged single-block files, since a
|
||||||
|
damaged block cannot be recovered. If you wish to minimise
|
||||||
|
any potential data loss through media or transmission errors,
|
||||||
|
you might consider compressing with a smaller
|
||||||
|
block size.
|
||||||
|
|
||||||
|
.SH PERFORMANCE NOTES
|
||||||
|
The sorting phase of compression gathers together similar strings in the
|
||||||
|
file. Because of this, files containing very long runs of repeated
|
||||||
|
symbols, like "aabaabaabaab ..." (repeated several hundred times) may
|
||||||
|
compress more slowly than normal. Versions 0.9.5 and above fare much
|
||||||
|
better than previous versions in this respect. The ratio between
|
||||||
|
worst-case and average-case compression time is in the region of 10:1.
|
||||||
|
For previous versions, this figure was more like 100:1. You can use the
|
||||||
|
\-vvvv option to monitor progress in great detail, if you want.
|
||||||
|
|
||||||
|
Decompression speed is unaffected by these phenomena.
|
||||||
|
|
||||||
|
.I bzip2
|
||||||
|
usually allocates several megabytes of memory to operate
|
||||||
|
in, and then charges all over it in a fairly random fashion. This means
|
||||||
|
that performance, both for compressing and decompressing, is largely
|
||||||
|
determined by the speed at which your machine can service cache misses.
|
||||||
|
Because of this, small changes to the code to reduce the miss rate have
|
||||||
|
been observed to give disproportionately large performance improvements.
|
||||||
|
I imagine
|
||||||
|
.I bzip2
|
||||||
|
will perform best on machines with very large caches.
|
||||||
|
|
||||||
|
.SH CAVEATS
|
||||||
|
I/O error messages are not as helpful as they could be.
|
||||||
|
.I bzip2
|
||||||
|
tries hard to detect I/O errors and exit cleanly, but the details of
|
||||||
|
what the problem is sometimes seem rather misleading.
|
||||||
|
|
||||||
|
This manual page pertains to version 1.0.3 of
|
||||||
|
.I bzip2.
|
||||||
|
Compressed data created by this version is entirely forwards and
|
||||||
|
backwards compatible with the previous public releases, versions
|
||||||
|
0.1pl2, 0.9.0, 0.9.5, 1.0.0, 1.0.1 and 1.0.2, but with the following
|
||||||
|
exception: 0.9.0 and above can correctly decompress multiple
|
||||||
|
concatenated compressed files. 0.1pl2 cannot do this; it will stop
|
||||||
|
after decompressing just the first file in the stream.
|
||||||
|
|
||||||
|
.I bzip2recover
|
||||||
|
versions prior to 1.0.2 used 32-bit integers to represent
|
||||||
|
bit positions in compressed files, so they could not handle compressed
|
||||||
|
files more than 512 megabytes long. Versions 1.0.2 and above use
|
||||||
|
64-bit ints on some platforms which support them (GNU supported
|
||||||
|
targets, and Windows). To establish whether or not bzip2recover was
|
||||||
|
built with such a limitation, run it without arguments. In any event
|
||||||
|
you can build yourself an unlimited version if you can recompile it
|
||||||
|
with MaybeUInt64 set to be an unsigned 64-bit integer.
|
||||||
|
|
||||||
|
|
||||||
|
|
||||||
|
.SH AUTHOR
|
||||||
|
Julian Seward, jsewardbzip.org.
|
||||||
|
|
||||||
|
http://www.bzip.org
|
||||||
|
|
||||||
|
The ideas embodied in
|
||||||
|
.I bzip2
|
||||||
|
are due to (at least) the following
|
||||||
|
people: Michael Burrows and David Wheeler (for the block sorting
|
||||||
|
transformation), David Wheeler (again, for the Huffman coder), Peter
|
||||||
|
Fenwick (for the structured coding model in the original
|
||||||
|
.I bzip,
|
||||||
|
and many refinements), and Alistair Moffat, Radford Neal and Ian Witten
|
||||||
|
(for the arithmetic coder in the original
|
||||||
|
.I bzip).
|
||||||
|
I am much
|
||||||
|
indebted for their help, support and advice. See the manual in the
|
||||||
|
source distribution for pointers to sources of documentation. Christian
|
||||||
|
von Roques encouraged me to look for faster sorting algorithms, so as to
|
||||||
|
speed up compression. Bela Lubkin encouraged me to improve the
|
||||||
|
worst-case compression performance.
|
||||||
|
Donna Robinson XMLised the documentation.
|
||||||
|
The bz* scripts are derived from those of GNU gzip.
|
||||||
|
Many people sent patches, helped
|
||||||
|
with portability problems, lent machines, gave advice and were generally
|
||||||
|
helpful.
|
||||||
152
man/man1/bzmore.1
Normal file
152
man/man1/bzmore.1
Normal file
@ -0,0 +1,152 @@
|
|||||||
|
.\"Shamelessly copied from zmore.1 by Philippe Troin <phil@fifi.org>
|
||||||
|
.\"for Debian GNU/Linux
|
||||||
|
.TH BZMORE 1
|
||||||
|
.SH NAME
|
||||||
|
bzmore, bzless \- file perusal filter for crt viewing of bzip2 compressed text
|
||||||
|
.SH SYNOPSIS
|
||||||
|
.B bzmore
|
||||||
|
[ name ... ]
|
||||||
|
.br
|
||||||
|
.B bzless
|
||||||
|
[ name ... ]
|
||||||
|
.SH NOTE
|
||||||
|
In the following description,
|
||||||
|
.I bzless
|
||||||
|
and
|
||||||
|
.I less
|
||||||
|
can be used interchangeably with
|
||||||
|
.I bzmore
|
||||||
|
and
|
||||||
|
.I more.
|
||||||
|
.SH DESCRIPTION
|
||||||
|
.I Bzmore
|
||||||
|
is a filter which allows examination of compressed or plain text files
|
||||||
|
one screenful at a time on a soft-copy terminal.
|
||||||
|
.I bzmore
|
||||||
|
works on files compressed with
|
||||||
|
.I bzip2
|
||||||
|
and also on uncompressed files.
|
||||||
|
If a file does not exist,
|
||||||
|
.I bzmore
|
||||||
|
looks for a file of the same name with the addition of a .bz2 suffix.
|
||||||
|
.PP
|
||||||
|
.I Bzmore
|
||||||
|
normally pauses after each screenful, printing --More--
|
||||||
|
at the bottom of the screen.
|
||||||
|
If the user then types a carriage return, one more line is displayed.
|
||||||
|
If the user hits a space,
|
||||||
|
another screenful is displayed. Other possibilities are enumerated later.
|
||||||
|
.PP
|
||||||
|
.I Bzmore
|
||||||
|
looks in the file
|
||||||
|
.I /etc/termcap
|
||||||
|
to determine terminal characteristics,
|
||||||
|
and to determine the default window size.
|
||||||
|
On a terminal capable of displaying 24 lines,
|
||||||
|
the default window size is 22 lines.
|
||||||
|
Other sequences which may be typed when
|
||||||
|
.I bzmore
|
||||||
|
pauses, and their effects, are as follows (\fIi\fP is an optional integer
|
||||||
|
argument, defaulting to 1) :
|
||||||
|
.PP
|
||||||
|
.IP \fIi\|\fP<space>
|
||||||
|
display
|
||||||
|
.I i
|
||||||
|
more lines, (or another screenful if no argument is given)
|
||||||
|
.PP
|
||||||
|
.IP ^D
|
||||||
|
display 11 more lines (a ``scroll'').
|
||||||
|
If
|
||||||
|
.I i
|
||||||
|
is given, then the scroll size is set to \fIi\|\fP.
|
||||||
|
.PP
|
||||||
|
.IP d
|
||||||
|
same as ^D (control-D)
|
||||||
|
.PP
|
||||||
|
.IP \fIi\|\fPz
|
||||||
|
same as typing a space except that \fIi\|\fP, if present, becomes the new
|
||||||
|
window size. Note that the window size reverts back to the default at the
|
||||||
|
end of the current file.
|
||||||
|
.PP
|
||||||
|
.IP \fIi\|\fPs
|
||||||
|
skip \fIi\|\fP lines and print a screenful of lines
|
||||||
|
.PP
|
||||||
|
.IP \fIi\|\fPf
|
||||||
|
skip \fIi\fP screenfuls and print a screenful of lines
|
||||||
|
.PP
|
||||||
|
.IP "q or Q"
|
||||||
|
quit reading the current file; go on to the next (if any)
|
||||||
|
.PP
|
||||||
|
.IP "e or q"
|
||||||
|
When the prompt --More--(Next file:
|
||||||
|
.IR file )
|
||||||
|
is printed, this command causes bzmore to exit.
|
||||||
|
.PP
|
||||||
|
.IP s
|
||||||
|
When the prompt --More--(Next file:
|
||||||
|
.IR file )
|
||||||
|
is printed, this command causes bzmore to skip the next file and continue.
|
||||||
|
.PP
|
||||||
|
.IP =
|
||||||
|
Display the current line number.
|
||||||
|
.PP
|
||||||
|
.IP \fIi\|\fP/expr
|
||||||
|
search for the \fIi\|\fP-th occurrence of the regular expression \fIexpr.\fP
|
||||||
|
If the pattern is not found,
|
||||||
|
.I bzmore
|
||||||
|
goes on to the next file (if any).
|
||||||
|
Otherwise, a screenful is displayed, starting two lines before the place
|
||||||
|
where the expression was found.
|
||||||
|
The user's erase and kill characters may be used to edit the regular
|
||||||
|
expression.
|
||||||
|
Erasing back past the first column cancels the search command.
|
||||||
|
.PP
|
||||||
|
.IP \fIi\|\fPn
|
||||||
|
search for the \fIi\|\fP-th occurrence of the last regular expression entered.
|
||||||
|
.PP
|
||||||
|
.IP !command
|
||||||
|
invoke a shell with \fIcommand\|\fP.
|
||||||
|
The character `!' in "command" are replaced with the
|
||||||
|
previous shell command. The sequence "\\!" is replaced by "!".
|
||||||
|
.PP
|
||||||
|
.IP ":q or :Q"
|
||||||
|
quit reading the current file; go on to the next (if any)
|
||||||
|
(same as q or Q).
|
||||||
|
.PP
|
||||||
|
.IP .
|
||||||
|
(dot) repeat the previous command.
|
||||||
|
.PP
|
||||||
|
The commands take effect immediately, i.e., it is not necessary to
|
||||||
|
type a carriage return.
|
||||||
|
Up to the time when the command character itself is given,
|
||||||
|
the user may hit the line kill character to cancel the numerical
|
||||||
|
argument being formed.
|
||||||
|
In addition, the user may hit the erase character to redisplay the
|
||||||
|
--More-- message.
|
||||||
|
.PP
|
||||||
|
At any time when output is being sent to the terminal, the user can
|
||||||
|
hit the quit key (normally control\-\\).
|
||||||
|
.I Bzmore
|
||||||
|
will stop sending output, and will display the usual --More--
|
||||||
|
prompt.
|
||||||
|
The user may then enter one of the above commands in the normal manner.
|
||||||
|
Unfortunately, some output is lost when this is done, due to the
|
||||||
|
fact that any characters waiting in the terminal's output queue
|
||||||
|
are flushed when the quit signal occurs.
|
||||||
|
.PP
|
||||||
|
The terminal is set to
|
||||||
|
.I noecho
|
||||||
|
mode by this program so that the output can be continuous.
|
||||||
|
What you type will thus not show on your terminal, except for the / and !
|
||||||
|
commands.
|
||||||
|
.PP
|
||||||
|
If the standard output is not a teletype, then
|
||||||
|
.I bzmore
|
||||||
|
acts just like
|
||||||
|
.I bzcat,
|
||||||
|
except that a header is printed before each file.
|
||||||
|
.SH FILES
|
||||||
|
.DT
|
||||||
|
/etc/termcap Terminal data base
|
||||||
|
.SH "SEE ALSO"
|
||||||
|
more(1), less(1), bzip2(1), bzdiff(1), bzgrep(1)
|
||||||
Loading…
x
Reference in New Issue
Block a user