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<TITLE>Linux in Plain English:Linux Commands Organized by Group</TITLE>

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

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

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

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

<!--PUBLISHER=IDG Books Worldwide, Inc.//-->

<!--IMPRINT=M & T Books//-->

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<P><BR></P>

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

<TABLE WIDTH="100%">

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<TD WIDTH="40%"><B>for (exp) [statements]</B>

<TD WIDTH="60%">Performs the <I>statements</I> if <I>exp</I> is true.

<TR>

<TD VALIGN="TOP"><B>if (exp) [statements] (else [statements])</B>

<TD>Performs the <I>statement</I> if the <I>exp</I> is true. Can also be used with the <B>else</B> extension; in this case, the alternate <I>statements</I> will be performed.

<TR>

<TD><B>while (exp) [statements]</B>

<TD>Repeats the <I>statement</I> if <I>exp</I> is true.

<TR>

<TD><B>break</B>

<TD>Ends a <B>for</B> or <B>while</B> statement.

<TR>

<TD VALIGN="TOP"><B>continue</B>

<TD>Jumps to the next iteration in a <B>for</B> statement. This is a GNU extension.

<TR>

<TD><B>define a(b)</B>

<TD>Defines the function <I>a</I> with the argument <I>b</I>.

</TABLE>

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

<TABLE WIDTH="100%">

<TR>

<TD WIDTH="20%"><B>halt</B>

<TD WIDTH="80%">Halts the <B>bc</B> command.

<TR>

<TD><B>limits</B>

<TD>Returns the local limits on the <B>bc</B> command.

<TR>

<TD VALIGN="TOP"><B>print list</B>

<TD>An odd command used to print a series of special characters. The <I>list</I> is a list of comma-delimited expressions and strings, printed in order.

</TABLE>

<P>Strings can include special characters, including the following:

</P>

<TABLE WIDTH="100%"><TR>

<TD WIDTH="20%"><B>a</B>

<TD WIDTH="80%">bell

<TR>

<TD><B>b</B>

<TD>backspace

<TR>

<TD><B>f</B>

<TD>form feed

<TR>

<TD><B>n</B>

<TD>newline

<TR>

<TD><B>r</B>

<TD>return

<TR>

<TD><B>q</B>

<TD>double quote

<TR>

<TD><B>t</B>

<TD>tab

<TR>

<TD><B>\</B>

<TD>backslash

</TABLE>

<P><FONT SIZE="+1"><B><I>OTHER OPERATORS AND KEYWORDS</I></B></FONT></P>

<TABLE WIDTH="100%">

<TR>

<TD WIDTH="20%">assignment

<TD WIDTH="80%">=&#43; =- =* =/ =^ =

<TR>

<TD>relational

<TD>&lt; &lt;= &gt; &gt;= == !=

<TR>

<TD>unary

<TD>- &#43;&#43; &#151;

</TABLE>

<P><FONT SIZE="+1"><B><I>MATH-LIBRARY FUNCTIONS</I></B></FONT></P>

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<TR>

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

<TD WIDTH="80%">Sine.

<TR>

<TD><B>c</B>

<TD>Cosine.

<TR>

<TD><B>a</B>

<TD>Arctangent.

<TR>

<TD><B>e</B>

<TD>Exponential; base <I>e</I>.

<TR>

<TD><B>l</B>

<TD>Natural logarithm.

<TR>

<TD><B>j(n,x)</B>

<TD>Bessel function.

</TABLE>

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

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<TD WIDTH="20%"><B>/* */</B>

<TD WIDTH="80%">Comment lines.

<TR>

<TD><B>&#123; &#125;</B>

<TD>Brackets statements.

<TR>

<TD><B>[ ]</B>

<TD>Array index.

</TABLE>

<P><FONT SIZE="+1"><B>bdftopcf......<TT>Bitmap Font Conversion</TT></B></FONT></P>

<IMG SRC="images/05-04i.jpg"><P><B>bdftopcf</B> <I>option(s) fontfile.bdf</I></P>

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

<P>The <B>bdftopcf</B> command converts fonts from the X Bitmap Distribution Format (BDF) to the Portable Compiled Format (PCF), which is more easily used by the X font server. PCF fonts can be read by any machine.</P>

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

<TABLE WIDTH="100%">

<TR>

<TD WIDTH="30%" VALIGN="TOP"><B>-i</B>

<TD WIDTH="70%">Inhibits computation of ink metrics. Bypassing computation can speed processing.

<TR>

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

<TD>Sets the font bit order to least significant bit (LSB) first.

<TR>

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

<TD>Sets the font byte order to least significant bit (LSB) first.

<TR>

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

<TD>Sets the font bit order to most significant bit (MSB) first.

<TR>

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

<TD>Sets the font byte order to most significant bit (MSB) first.

<TR>

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

<TD>Specifies the name of the output file.

<TR>

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

<TD>Padding for the font glyph is set to <I>n</I>. Each glyph has each scanline padded to 1, 2, 4, or 8 bytes.

<TR>

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

<TD>Convert fonts to &#147;terminal fonts&#148; when possible. This option allows fonts to rendered more quickly by the font server.

<TR>

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

<TD>Sets the font scanline unit to <I>n</I>. This option is necessary when the font bit order is different than the font byte order; <I>n</I> can be 1, 2, or 4 bytes.

</TABLE>

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

<!-- CODE SNIP //-->

<PRE>

$ bdftopcf -t -o fontfile.pcf fontfile.dbf

</PRE>

<!-- END CODE SNIP //-->

<P><FONT SIZE="+1"><B>bitmap......<TT>Bitmap Editor</TT></B></FONT></P>

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

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

<P>The <B>bitmap</B> program is used to create and edit bitmaps. <I>Bitmaps</I> are image files laid out in a grid and used in the X Window System for a variety of purposes, from icons and cursors to Web-page graphic elements. They are stored as actual C code, which can be inserted directly into programs.</P>

<P>This program can specify a &#147;hot spot&#148; for use with a cursor, which tells the window manager where the cursor is specifically pointing, such as a tip of an arrow or the middle of a crosshair.</P>

<P>The basename is used with the C code input file.</P>

<P>To see how the image will actually appear, press <B>Alt-I</B>.</P>

<P>There are a number of commands available when this program is actually running, such as inverting the present image and marking a section of the bitmap. These are available through buttons on the left side of the window.</P><P><BR></P>

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