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<!--ISBN=1558285423//-->

<!--TITLE=Linux in Plain English//-->

<!--AUTHOR=Patrick Volkerding//-->

<!--AUTHOR=Kevin Reichard//-->

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<P><BR></P>

<P><FONT SIZE="+1"><B>rm......<TT>Remove Files</TT></B></FONT></P>

<IMG SRC="images/05-101i.jpg"><P><B>rm</B> <I>option(s) filename</I></P>

<P><FONT SIZE="+1"><B><I>PURPOSE</I></B></FONT></P>

<P>The <B>rm</B> command removes directories from the Linux filesystem. You are prompted before the file is actually removed.</P>

<P>Unlike the standard UNIX versions of <B>rm</B>, this GNU version does not remove directories by default.</P>

<P><FONT SIZE="+1"><B><I>OPTIONS</I></B></FONT></P>

<TABLE WIDTH="100%">

<TR>

<TD WIDTH="20%" VALIGN="TOP"><B>-d</B>

<TD WIDTH="80%">Removes linked directories with the <B>unink</B> command instead of the <B>rmdir</B> command. (Only root users have access to the <B>-d</B> option.)

<TR>

<TD><B>-f</B>

<TD>Ignores nonexistent files.

<TR>

<TD><B>-i</B>

<TD>Explicitly sets prompting before removing files.

<TR>

<TD><B>-r</B>

<TD>Removes the contents of directories recursively.

<TR>

<TD VALIGN="TOP"><B>-v</B>

<TD>Works in verbose mode, printing the name of each file before removing it.

</TABLE>

<P><FONT SIZE="+1"><B>rmdir......<TT>Remove Directory</TT></B></FONT></P>

<IMG SRC="images/05-102i.jpg"><P><B>rmdir</B> <I>option(s) directory</I></P>

<P><FONT SIZE="+1"><B><I>PURPOSE</I></B></FONT></P>

<P>The <B>rmdir</B> command removes empty directories. Directories with contents will not be deleted.</P>

<P><FONT SIZE="+1"><B><I>OPTIONS</I></B></FONT></P>

<TABLE WIDTH="100%">

<TR>

<TD WIDTH="20%" VALIGN="TOP"><B>-p</B>

<TD WIDTH="80%">Removes parent directories if they&#146;re mentioned as part of the command line.

</TABLE>

<P><FONT SIZE="+1"><B>shrinkfile......<TT>Shrink File</TT></B></FONT></P>

<P><B>shrinkfile</B> <I>option(s) filename</I></P>

<P><FONT SIZE="+1"><B><I>PURPOSE</I></B></FONT></P>

<P>The <B>shrinkfile</B> command shrinks a file on a line boundary, preserving the data at the end of the file. Truncation is performed on line boundaries, where a line is a series of bytes ending with a newline. There is no line length restriction and files may contain any binary data.</P>

<P><FONT SIZE="+1"><B><I>OPTIONS</I></B></FONT></P>

<TABLE WIDTH="100%">

<TR>

<TD WIDTH="20%"><B>-s num</B>

<TD WIDTH="80%">Changes the maximum size to <I>num</I>.

<TR>

<TD><B>-v</B>

<TD>Prints a status line if a file was shrunk.

</TABLE>

<P><FONT SIZE="+1"><B>size......<TT>Lists Sizes</TT></B></FONT></P>

<IMG SRC="images/05-103i.jpg"><P><B>size</B> <I>option(s) object-file(s)</I></P>

<P><FONT SIZE="+1"><B><I>PURPOSE</I></B></FONT></P>

<P>The <B>size</B> command lists the sections sizes and the total size for the <I>object-file(s)</I> listed on the command line. One line of output is generated for each file.</P>

<P><FONT SIZE="+1"><B><I>OPTIONS</I></B></FONT></P>

<TABLE WIDTH="100%">

<TR>

<TD WIDTH="20%"><B>-A</B>

<TD WIDTH="80%">Output resembles System V <B>size</B> output.

<TR>

<TD><B>-B</B>

<TD>Output resembles Berkeley <B>size</B> format.

<TR>

<TD><B>-d</B>

<TD>Sizes are listed in decimals.

<TR>

<TD><B>-o</B>

<TD>Sizes are listed in octals.

<TR>

<TD><B>-x</B>

<TD>Sizes are listed in hexadecimal.

<TR>

<TD><B>--target <I>bfdname</I></B>

<TD VALIGN="TOP">Specifies object-code format as <I>bfdname</I>.

</TABLE>

<P><FONT SIZE="+1"><B>sq......<TT>Squeeze Word List</TT></B></FONT></P>

<P><B>sq</B> <I>inputfile outputfile</I></P>

<P><FONT SIZE="+1"><B><I>PURPOSE</I></B></FONT></P>

<P>The <B>sq</B> command squeezes a sorted word list. It&#146;s generally used for large text files, such as dictionaries. The squeezing is achieved by eliminating common prefixes and replacing them with a single character, which encodes the number of characters shared with the preceding word.</P>

<P><FONT SIZE="+1"><B><I>RELATED COMMAND</I></B></FONT></P>

<DL>

<DD><B>unsq</B>

</DL>

<P><FONT SIZE="+1"><B>sum......<TT>File Checksum</TT></B></FONT></P>

<IMG SRC="images/05-104i.jpg"><P><B>sum</B> <I>option(s) filename(s)</I></P>

<P><FONT SIZE="+1"><B><I>PURPOSE</I></B></FONT></P>

<P>The <B>sum</B> performs a checksum on a file and counts the blocks. It computes a 16-bit checksum for each named file. It prints the checksum for each file along with the number of blocks in the file. The GNU version of <B>sum</B> computes checksums using an algorithm that is compatible with the BSD <B>sum</B> and prints file sizes in units of 1K blocks.</P>

<P><FONT SIZE="+1"><B><I>OPTIONS</I></B></FONT></P>

<TABLE WIDTH="100%">

<TR>

<TD WIDTH="20%"><B>-r</B>

<TD WIDTH="80%">Uses the BSD-compatible algorithm, which is the default.

<TR>

<TD VALIGN="TOP"><B>-s</B>

<TD>Uses a System V-compatible algorithm and prints out filesizes in 512-byte blocks.

</TABLE>

<P><FONT SIZE="+1"><B>test......<TT>Check File Type</TT></B></FONT></P>

<IMG SRC="images/05-105i.jpg"><P><B>test</B> <I>expression</I></P>

<P><FONT SIZE="+1"><B><I>PURPOSE</I></B></FONT></P>

<P>The <B>test</B> command returns a status of 0 (true) or 1 (false) depending on the evaluation of the conditional <I>expression</I>, which can be unary or binary. There is a long list of expressions available; check the online-manual or <B>info</B> pages for more information.</P>

<P><FONT SIZE="+1"><B>unsq......<TT>Unsqueeze Word List</TT></B></FONT></P>

<P><B>unsq</B> <I>inputfile outputfile</I></P>

<P><FONT SIZE="+1"><B><I>PURPOSE</I></B></FONT></P>

<P>The <B>unsq</B> command unsqueezes a sorted word list that&#146;s been squeezed by <B>sq</B>.</P>

<P><FONT SIZE="+1"><B><I>RELATED COMMAND</I></B></FONT></P>

<DL>

<DD><B>sq</B>

</DL>

<P><FONT SIZE="+1"><B>unzip......<TT>Unzip File</TT></B></FONT></P>

<P><B>unzip</B> <I>option(s)</I></P>

<P><FONT SIZE="+1"><B><I>PURPOSE</I></B></FONT></P>

<P>The <B>unzip</B> command will unzip a file that&#146;s been compressed using the PKZip or WinZip ZIP format found on MS-DOS/Windows systems. See the online-manual pages for more information on the many options.</P>

<P><FONT SIZE="+1"><B><I>RELATED COMMAND</I></B></FONT></P>

<DL>

<DD><B>unzipsfx</B>

</DL>

<P><FONT SIZE="+1"><B>unzipsfx......<TT>Self-Extracting ZIP</TT></B></FONT></P>

<P><B>unzipsfx</B> <I>option(s)</I></P>

<P><FONT SIZE="+1"><B><I>PURPOSE</I></B></FONT></P>

<P>The <B>unzipsfx</B> creates a new archive file with <B>unzip</B> prepended to existing ZIP archives, forming self-extracting archives. See the online-manual pages for more information on the many options.</P>

<P><FONT SIZE="+1"><B><I>RELATED COMMAND</I></B></FONT></P>

<DL>

<DD><B>unzip</B>

</DL>

<P><FONT SIZE="+1"><B>updatedb......<TT>Update Filename Database</TT></B></FONT></P>

<IMG SRC="images/05-106i.jpg"><P><B>updatedb</B> <I>option(s)</I></P>

<P><FONT SIZE="+1"><B><I>PURPOSE</I></B></FONT></P>

<P>The <B>updatedb</B> command updates a filename database used by the <B>locate</B> command. This database contains lists of files that were in particular directory trees when the databases were last updated.</P>

<P><FONT SIZE="+1"><B><I>OPTIONS</I></B></FONT></P>

<TABLE WIDTH="100%">

<TR>

<TD WIDTH="40%" VALIGN="TOP"><B>--localpaths=<I>path1 path2</I></B>

<TD WIDTH="60%">Specifies nonnetwork directories to put in the database.

<TR>

<TD VALIGN="TOP"><B>--netpaths=<I>path1 path2</I></B>

<TD>Specifies network directories to put in the database.

<TR>

<TD VALIGN="TOP"><B>--netuser=<I>user</I></B>

<TD>Specifies the user to search network directories as.

<TR>

<TD VALIGN="TOP"><B>--old-format</B>

<TD>Creates the database in the old format instead of the new one.

<TR>

<TD><B>--output=<I>dbfile</I></B>

<TD>Specifies the database file to build.

<TR>

<TD VALIGN="TOP"><B>--prunepaths=<I>path1 path2</I></B>

<TD>Specifies directories not to put in the database.

</TABLE>

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