Filter-Mode.html 6.7 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134
  1. <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html401/loose.dtd">
  2. <html>
  3. <!-- Created on December 10, 2012 by texi2html 1.82
  4. texi2html was written by:
  5. Lionel Cons <[email protected]> (original author)
  6. Karl Berry <[email protected]>
  7. Olaf Bachmann <[email protected]>
  8. and many others.
  9. Maintained by: Many creative people.
  10. Send bugs and suggestions to <[email protected]>
  11. -->
  12. <head>
  13. <title>avram - a virtual machine code interpreter: 1.2.1 Filter Mode</title>
  14. <meta name="description" content="avram - a virtual machine code interpreter: 1.2.1 Filter Mode">
  15. <meta name="keywords" content="avram - a virtual machine code interpreter: 1.2.1 Filter Mode">
  16. <meta name="resource-type" content="document">
  17. <meta name="distribution" content="global">
  18. <meta name="Generator" content="texi2html 1.82">
  19. <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
  20. <style type="text/css">
  21. <!--
  22. a.summary-letter {text-decoration: none}
  23. blockquote.smallquotation {font-size: smaller}
  24. pre.display {font-family: serif}
  25. pre.format {font-family: serif}
  26. pre.menu-comment {font-family: serif}
  27. pre.menu-preformatted {font-family: serif}
  28. pre.smalldisplay {font-family: serif; font-size: smaller}
  29. pre.smallexample {font-size: smaller}
  30. pre.smallformat {font-family: serif; font-size: smaller}
  31. pre.smalllisp {font-size: smaller}
  32. span.roman {font-family:serif; font-weight:normal;}
  33. span.sansserif {font-family:sans-serif; font-weight:normal;}
  34. ul.toc {list-style: none}
  35. -->
  36. </style>
  37. </head>
  38. <body lang="en" bgcolor="#FFFFFF" text="#000000" link="#0000FF" vlink="#800080" alink="#FF0000">
  39. <a name="Filter-Mode"></a>
  40. <table cellpadding="1" cellspacing="1" border="0">
  41. <tr><td valign="middle" align="left">[<a href="Modes-of-Operation.html#Modes-of-Operation" title="Previous section in reading order"> &lt; </a>]</td>
  42. <td valign="middle" align="left">[<a href="Parameter-Mode.html#Parameter-Mode" title="Next section in reading order"> &gt; </a>]</td>
  43. <td valign="middle" align="left"> &nbsp; </td>
  44. <td valign="middle" align="left">[<a href="User-Manual.html#User-Manual" title="Beginning of this chapter or previous chapter"> &lt;&lt; </a>]</td>
  45. <td valign="middle" align="left">[<a href="Modes-of-Operation.html#Modes-of-Operation" title="Up section"> Up </a>]</td>
  46. <td valign="middle" align="left">[<a href="Virtual-Machine-Specification.html#Virtual-Machine-Specification" title="Next chapter"> &gt;&gt; </a>]</td>
  47. <td valign="middle" align="left"> &nbsp; </td>
  48. <td valign="middle" align="left"> &nbsp; </td>
  49. <td valign="middle" align="left"> &nbsp; </td>
  50. <td valign="middle" align="left"> &nbsp; </td>
  51. <td valign="middle" align="left">[<a href="avram.html#Top" title="Cover (top) of document">Top</a>]</td>
  52. <td valign="middle" align="left">[<a href="avram_toc.html#SEC_Contents" title="Table of contents">Contents</a>]</td>
  53. <td valign="middle" align="left">[<a href="Function-Index.html#Function-Index" title="Index">Index</a>]</td>
  54. <td valign="middle" align="left">[<a href="avram_abt.html#SEC_About" title="About (help)"> ? </a>]</td>
  55. </tr></table>
  56. <hr size="1">
  57. <a name="Filter-Mode-1"></a>
  58. <h3 class="subsection">1.2.1 Filter Mode</h3>
  59. <a name="index-filter-mode"></a>
  60. <a name="index-modes-2"></a>
  61. <p>In filter mode, the argument to the function given by the virtual code
  62. is taken from standard input, and the result is written to standard
  63. output, except for error messages resulting from a failure to evaluate
  64. the function, which are written to standard error.
  65. See section <a href="Diagnostics.html#Diagnostics">Diagnostics</a>. Filter mode is indicated whenever these three
  66. conditions are all met.
  67. </p>
  68. <ul>
  69. <li>
  70. Either at least one of the filter mode options appears on the command
  71. line preceding the first filename parameter, or there are no options at
  72. all. See section <a href="Filter-Mode-Options.html#Filter-Mode-Options">Filter Mode Options</a>.
  73. </li><li>
  74. Exactly one filename parameter appears on the command line,
  75. which is the name of the virtual machine code file.
  76. </li><li>
  77. Either the filename comes last on the command line, or the
  78. &lsquo;<samp>--unparameterized</samp>&rsquo; option precedes it, causing
  79. everything following it to be ignored.
  80. </li></ul>
  81. <p>Examples:
  82. </p>
  83. <dl compact="compact">
  84. <dt> <kbd>avram mynewapp &lt; inputfilename</kbd></dt>
  85. <dd><a name="index-standard-input-1"></a>
  86. <p>In this example, filter mode is recognized by default because there are
  87. no options or input files on the command line to indicate
  88. otherwise. (The input file redirected into standard input is not treated
  89. by the shell as a command line argument.)
  90. </p></dd>
  91. <dt> <kbd>cat somefile | avram -r coolprog &gt; outputfile</kbd></dt>
  92. <dd><p>In this example, the &lsquo;<samp>-r</samp>&rsquo; option gives it away, being one of the
  93. filter mode options, in addition to the fact that there are no input
  94. file parameters or application-specific options.
  95. </p></dd>
  96. <dt> <kbd>avram -u devilmaycare.avm --bogusoption ignoredparameter</kbd></dt>
  97. <dd><p>In this case, filter mode is forced by the &lsquo;<samp>-u</samp>&rsquo;
  98. option despite indications to the contrary.
  99. </p></dd>
  100. </dl>
  101. <hr size="1">
  102. <table cellpadding="1" cellspacing="1" border="0">
  103. <tr><td valign="middle" align="left">[<a href="Modes-of-Operation.html#Modes-of-Operation" title="Previous section in reading order"> &lt; </a>]</td>
  104. <td valign="middle" align="left">[<a href="Parameter-Mode.html#Parameter-Mode" title="Next section in reading order"> &gt; </a>]</td>
  105. <td valign="middle" align="left"> &nbsp; </td>
  106. <td valign="middle" align="left">[<a href="User-Manual.html#User-Manual" title="Beginning of this chapter or previous chapter"> &lt;&lt; </a>]</td>
  107. <td valign="middle" align="left">[<a href="Modes-of-Operation.html#Modes-of-Operation" title="Up section"> Up </a>]</td>
  108. <td valign="middle" align="left">[<a href="Virtual-Machine-Specification.html#Virtual-Machine-Specification" title="Next chapter"> &gt;&gt; </a>]</td>
  109. <td valign="middle" align="left"> &nbsp; </td>
  110. <td valign="middle" align="left"> &nbsp; </td>
  111. <td valign="middle" align="left"> &nbsp; </td>
  112. <td valign="middle" align="left"> &nbsp; </td>
  113. <td valign="middle" align="left">[<a href="avram.html#Top" title="Cover (top) of document">Top</a>]</td>
  114. <td valign="middle" align="left">[<a href="avram_toc.html#SEC_Contents" title="Table of contents">Contents</a>]</td>
  115. <td valign="middle" align="left">[<a href="Function-Index.html#Function-Index" title="Index">Index</a>]</td>
  116. <td valign="middle" align="left">[<a href="avram_abt.html#SEC_About" title="About (help)"> ? </a>]</td>
  117. </tr></table>
  118. <p>
  119. <font size="-1">
  120. This document was generated on <i>December 10, 2012</i> using <a href="http://www.nongnu.org/texi2html/"><i>texi2html 1.82</i></a>.
  121. </font>
  122. <br>
  123. </p>
  124. </body>
  125. </html>