busybox.html

手机嵌入式Linux下可用的busybox源码

        conv=sync       pad blocks with zeros</PRE>
<P>Numbers may be suffixed by c (x1), w (x2), b (x512), kD (x1000), k (x1024),
MD (x1000000), M (x1048576), GD (x1000000000) or G (x1073741824).</P>
<P>Example:</P>
<PRE>
        $ dd if=/dev/zero of=/dev/ram1 bs=1M count=4
        4+0 records in
        4+0 records out</PRE>
<P>-------------------------------</P>
<P></P>
<DT><STRONG><A NAME="item_deallocvt"><STRONG>deallocvt</STRONG></A></STRONG><BR>
<DD>
deallocvt N
<P>Deallocate unused virtual terminal /dev/ttyN</P>
<P>-------------------------------</P>
<P></P>
<DT><STRONG><A NAME="item_df"><STRONG>df</STRONG></A></STRONG><BR>
<DD>
df [<STRONG>-hmk</STRONG>] [FILESYSTEM ...]
<P>Print the filesystem space used and space available.</P>
<P>Options:</P>
<PRE>
        -h      print sizes in human readable format (e.g., 1K 243M 2G )
        -m      print sizes in megabytes
        -k      print sizes in kilobytes(default)</PRE>
<P>Example:</P>
<PRE>
        $ df
        Filesystem           1k-blocks      Used Available Use% Mounted on
        /dev/sda3              8690864   8553540    137324  98% /
        /dev/sda1                64216     36364     27852  57% /boot
        $ df /dev/sda3
        Filesystem           1k-blocks      Used Available Use% Mounted on
        /dev/sda3              8690864   8553540    137324  98% /</PRE>
<P>-------------------------------</P>
<P></P>
<DT><STRONG><A NAME="item_dirname"><STRONG>dirname</STRONG></A></STRONG><BR>
<DD>
dirname [FILENAME ...]
<P>Strips non-directory suffix from FILENAME</P>
<P>Example:</P>
<PRE>
        $ dirname /tmp/foo
        /tmp
        $ dirname /tmp/foo/
        /tmp</PRE>
<P>-------------------------------</P>
<P></P>
<DT><STRONG><A NAME="item_dmesg"><STRONG>dmesg</STRONG></A></STRONG><BR>
<DD>
dmesg [<STRONG>-c</STRONG>] [<STRONG>-n</STRONG> LEVEL] [<STRONG>-s</STRONG> SIZE]
<P>Prints or controls the kernel ring buffer</P>
<P>Options:</P>
<PRE>
        -c              Clears the ring buffer's contents after printing
        -n LEVEL        Sets console logging level
        -s SIZE         Use a buffer of size SIZE</PRE>
<P>-------------------------------</P>
<P></P>
<DT><STRONG><A NAME="item_dos2unix"><STRONG>dos2unix</STRONG></A></STRONG><BR>
<DD>
dos2unix [option] [FILE]
<P>Converts FILE from dos format to unix format.  When no option
is given, the input is converted to the opposite output format.
When no file is given, uses stdin for input and stdout for output.</P>
<P>Options:</P>
<PRE>
        -u      output will be in UNIX format
        -d      output will be in DOS format</PRE>
<P>-------------------------------</P>
<P></P>
<DT><STRONG><A NAME="item_dpkg"><STRONG>dpkg</STRONG></A></STRONG><BR>
<DD>
dpkg <STRONG>-i</STRONG> package_file
[<STRONG>-CPru</STRONG>] package_name
<PRE>
        -i      Install the package
        -C      Configure an unpackaged package
        -P      Purge all files of a package
        -r      Remove all but the configuration files for a package
        -u      Unpack a package, but dont configure it</PRE>
<P>-------------------------------</P>
<P></P>
<DT><STRONG><A NAME="item_dpkg_deb"><STRONG>dpkg_deb</STRONG></A></STRONG><BR>
<DD>
dpkg_deb [<STRONG>-cefItxX</STRONG>] FILE [argument]
<P>Perform actions on debian packages (.debs)</P>
<P>Options:</P>
<PRE>
        -c      List contents of filesystem tree
        -e      Extract control files to [argument] directory
        -f      Display control field name starting with [argument]
        -I      Display the control filenamed [argument]
        -t      Extract filesystem tree to stdout in tar format
        -x      Extract packages filesystem tree to directory
        -X      Verbose extract</PRE>
<P>Example:</P>
<PRE>
        $ dpkg-deb -X ./busybox_0.48-1_i386.deb /tmp</PRE>
<P>-------------------------------</P>
<P></P>
<DT><STRONG><A NAME="item_du"><STRONG>du</STRONG></A></STRONG><BR>
<DD>
du [<STRONG>-lsxhmk</STRONG>] [FILE]...
<P>Summarizes disk space used for each FILE and/or directory.
Disk space is printed in units of 1024 bytes.</P>
<P>Options:</P>
<PRE>
        -l      count sizes many times if hard linked
        -s      display only a total for each argument
        -h      print sizes in human readable format (e.g., 1K 243M 2G )
        -m      print sizes in megabytes
        -x      skip directories on different filesystems
        -k      print sizes in kilobytes(default)</PRE>
<P>Example:</P>
<PRE>
        $ du
        16      ./CVS
        12      ./kernel-patches/CVS
        80      ./kernel-patches
        12      ./tests/CVS
        36      ./tests
        12      ./scripts/CVS
        16      ./scripts
        12      ./docs/CVS
        104     ./docs
        2417    .</PRE>
<P>-------------------------------</P>
<P></P>
<DT><STRONG><A NAME="item_dumpkmap"><STRONG>dumpkmap</STRONG></A></STRONG><BR>
<DD>
dumpkmap &gt; keymap
<P>Prints out a binary keyboard translation table to standard output.</P>
<P>Example:</P>
<PRE>
        $ dumpkmap &gt; keymap</PRE>
<P>-------------------------------</P>
<P></P>
<DT><STRONG><A NAME="item_dutmp"><STRONG>dutmp</STRONG></A></STRONG><BR>
<DD>
dutmp [FILE]
<P>Dump utmp file format (pipe delimited) from FILE
or stdin to stdout.  (i.e., 'dutmp /var/run/utmp')</P>
<P>Example:</P>
<PRE>
        $ dutmp /var/run/utmp
        8|7||si|||0|0|0|955637625|760097|0
        2|0|~|~~|reboot||0|0|0|955637625|782235|0
        1|20020|~|~~|runlevel||0|0|0|955637625|800089|0
        8|125||l4|||0|0|0|955637629|998367|0
        6|245|tty1|1|LOGIN||0|0|0|955637630|998974|0
        6|246|tty2|2|LOGIN||0|0|0|955637630|999498|0
        7|336|pts/0|vt00andersen|andersen|:0.0|0|0|0|955637763|0|0</PRE>
<P>-------------------------------</P>
<P></P>
<DT><STRONG><A NAME="item_echo"><STRONG>echo</STRONG></A></STRONG><BR>
<DD>
echo [<STRONG>-neE</STRONG>] [ARG ...]
<P>Prints the specified ARGs to stdout</P>
<P>Options:</P>
<PRE>
        -n      suppress trailing newline
        -e      interpret backslash-escaped characters (i.e., \t=tab)
        -E      disable interpretation of backslash-escaped characters</PRE>
<P>Example:</P>
<PRE>
        $ echo &quot;Erik is cool&quot;
        Erik is cool
        $  echo -e &quot;Erik\nis\ncool&quot;
        Erik
        is
        cool
        $ echo &quot;Erik\nis\ncool&quot;
        Erik\nis\ncool</PRE>
<P>-------------------------------</P>
<P></P>
<DT><STRONG><A NAME="item_env"><STRONG>env</STRONG></A></STRONG><BR>
<DD>
env [<STRONG>-iu</STRONG>] [-] [name=value]... [command]
<P>Prints the current environment or runs a program after setting
up the specified environment.</P>
<P>Options:</P>
<PRE>
        -, -i   start with an empty environment
        -u      remove variable from the environment</PRE>
<P>-------------------------------</P>
<P></P>
<DT><STRONG><A NAME="item_expr"><STRONG>expr</STRONG></A></STRONG><BR>
<DD>
expr EXPRESSION
<P>Prints the value of EXPRESSION to standard output.</P>
<P>EXPRESSION may be:</P>
<PRE>
        ARG1 |  ARG2    ARG1 if it is neither null nor 0, otherwise ARG2
        ARG1 &amp;  ARG2    ARG1 if neither argument is null or 0, otherwise 0
        ARG1 &lt;  ARG2    ARG1 is less than ARG2
        ARG1 &lt;= ARG2    ARG1 is less than or equal to ARG2
        ARG1 =  ARG2    ARG1 is equal to ARG2
        ARG1 != ARG2    ARG1 is unequal to ARG2
        ARG1 &gt;= ARG2    ARG1 is greater than or equal to ARG2
        ARG1 &gt;  ARG2    ARG1 is greater than ARG2
        ARG1 +  ARG2    arithmetic sum of ARG1 and ARG2
        ARG1 -  ARG2    arithmetic difference of ARG1 and ARG2
        ARG1 *  ARG2    arithmetic product of ARG1 and ARG2
        ARG1 /  ARG2    arithmetic quotient of ARG1 divided by ARG2
        ARG1 %  ARG2    arithmetic remainder of ARG1 divided by ARG2
        STRING : REGEXP             anchored pattern match of REGEXP in STRING
        match STRING REGEXP         same as STRING : REGEXP
        substr STRING POS LENGTH    substring of STRING, POS counted from 1
        index STRING CHARS          index in STRING where any CHARS is found,
                                    or 0
        length STRING               length of STRING
        quote TOKEN                 interpret TOKEN as a string, even if
                                    it is a keyword like `match' or an
                                    operator like `/'
        ( EXPRESSION )              value of EXPRESSION</PRE>
<P>Beware that many operators need to be escaped or quoted for shells.
Comparisons are arithmetic if both ARGs are numbers, else
lexicographical.  Pattern matches return the string matched between 
\( and \) or null; if \( and \) are not used, they return the number 
of characters matched or 0.</P>
<P>-------------------------------</P>
<P></P>
<DT><STRONG><A NAME="item_false"><STRONG>false</STRONG></A></STRONG><BR>
<DD>
false
<P>Return an exit code of FALSE (1).</P>
<P>Example:</P>
<PRE>
        $ false
        $ echo $?
        1</PRE>
<P>-------------------------------</P>
<P></P>
<DT><STRONG><A NAME="item_fbset"><STRONG>fbset</STRONG></A></STRONG><BR>
<DD>
fbset [options] [mode]
<P>Show and modify frame buffer settings</P>
<P>Example:</P>
<PRE>
        $ fbset
        mode &quot;1024x768-76&quot;
                # D: 78.653 MHz, H: 59.949 kHz, V: 75.694 Hz
                geometry 1024 768 1024 768 16
                timings 12714 128 32 16 4 128 4
                accel false
                rgba 5/11,6/5,5/0,0/0
        endmode</PRE>
<P>-------------------------------</P>
<P></P>
<DT><STRONG><A NAME="item_fdflush"><STRONG>fdflush</STRONG></A></STRONG><BR>
<DD>
fdflush DEVICE
<P>Forces floppy disk drive to detect disk change</P>
<P>-------------------------------</P>
<P></P>
<DT><STRONG><A NAME="item_find"><STRONG>find</STRONG></A></STRONG><BR>
<DD>
find [PATH...] [EXPRESSION]
<P>Search for files in a directory hierarchy.  The default PATH is
the current directory; default EXPRESSION is '<STRONG>-print</STRONG>'</P>
<P>EXPRESSION may consist of:</P>
<PRE>
        -follow         Dereference symbolic links.
        -name PATTERN   File name (leading directories removed) matches PATTERN.
        -print          Print (default and assumed).</PRE>
<PRE>
        -type X         Filetype matches X (where X is one of: f,d,l,b,c,...)
        -perm PERMS     Permissions match any of (+NNN); all of (-NNN);
                        or exactly (NNN)
        -mtime TIME     Modified time is greater than (+N); less than (-N);
                        or exactly (N) days
        -newer FILE     Modified time is more recent than FILE's</PRE>
<P>Example:</P>
<PRE>
        $ find / -name /etc/passwd
        /etc/passwd</PRE>
<P>-------------------------------</P>
<P></P>
<DT><STRONG><A NAME="item_free"><STRONG>free</STRONG></A></STRONG><BR>
<DD>
free
<P>Displays the amount of free and used system memory</P>
<P>Example:</P>
<PRE>
        $ free
                      total         used         free       shared      buffers
          Mem:       257628       248724         8904        59644        93124
         Swap:       128516         8404       120112
        Total:       386144       257128       129016</PRE>
<P>-------------------------------</P>
<P></P>
<DT><STRONG><A NAME="item_freeramdisk"><STRONG>freeramdisk</STRONG></A></STRONG><BR>
<DD>
freeramdisk DEVICE
<P>Frees all memory used by the specified ramdisk.</P>
<P>Example:</P>
<PRE>
        $ freeramdisk /dev/ram2</PRE>
<P>-------------------------------</P>
<P></P>
<DT><STRONG><A NAME="item_fsck_minix"><STRONG>fsck_minix</STRONG></A></STRONG><BR>
<DD>
fsck_minix [<STRONG>-larvsmf</STRONG>] /dev/name
<P>Performs a consistency check for MINIX filesystems.</P>
<P>Options:</P>
<PRE>
        -l      Lists all filenames
        -r      Perform interactive repairs
        -a      Perform automatic repairs
        -v      verbose
        -s      Outputs super-block information
        -m      Activates MINIX-like &quot;mode not cleared&quot; warnings
        -f      Force file system check.</PRE>
<P>-------------------------------</P>
<P></P>
<DT><STRONG><A NAME="item_getopt"><STRONG>getopt</STRONG></A></STRONG><BR>
<DD>
getopt [OPTIONS]...
<P>Parse command options</P>
<PRE>
        -a, --alternative               Allow long options starting with single -
        -l, --longoptions=longopts      Long options to be recognized
        -n, --name=progname             The name under which errors are reported
        -o, --options=optstring Short options to be recognized
        -q, --quiet                     Disable error reporting by getopt(3)
        -Q, --quiet-output              No normal output
        -s, --shell=shell               Set shell quoting conventions
        -T, --test                      Test for getopt(1) version
        -u, --unqote                    Do not quote the output</PRE>