1 | =head1 NAME |
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2 | |
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3 | perlfaq - frequently asked questions about Perl ($Date: 2000-04-07 20:44:18 $) |
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4 | |
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5 | =head1 DESCRIPTION |
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6 | |
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7 | This document is structured into the following sections: |
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8 | |
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9 | =over |
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10 | |
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11 | =item perlfaq: Structural overview of the FAQ. |
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12 | |
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13 | This document. |
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14 | |
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15 | =item L<perlfaq1>: General Questions About Perl |
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16 | |
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17 | Very general, high-level information about Perl. |
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18 | |
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19 | =over 4 |
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20 | |
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21 | =item * What is Perl? |
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22 | |
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23 | =item * Who supports Perl? Who develops it? Why is it free? |
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24 | |
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25 | =item * Which version of Perl should I use? |
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26 | |
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27 | =item * What are perl4 and perl5? |
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28 | |
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29 | =item * What is perl6? |
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30 | |
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31 | =item * How stable is Perl? |
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32 | |
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33 | =item * Is Perl difficult to learn? |
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34 | |
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35 | =item * How does Perl compare with other languages like Java, Python, REXX, Scheme, or Tcl? |
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36 | |
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37 | =item * Can I do [task] in Perl? |
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38 | |
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39 | =item * When shouldn't I program in Perl? |
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40 | |
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41 | =item * What's the difference between "perl" and "Perl"? |
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42 | |
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43 | =item * Is it a Perl program or a Perl script? |
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44 | |
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45 | =item * What is a JAPH? |
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46 | |
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47 | =item * Where can I get a list of Larry Wall witticisms? |
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48 | |
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49 | =item * How can I convince my sysadmin/supervisor/employees to use version (5/5.005/Perl instead of some other language)? |
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50 | |
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51 | =back |
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52 | |
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53 | |
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54 | =item L<perlfaq2>: Obtaining and Learning about Perl |
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55 | |
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56 | Where to find source and documentation to Perl, support, |
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57 | and related matters. |
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58 | |
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59 | =over 4 |
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60 | |
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61 | =item * What machines support Perl? Where do I get it? |
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62 | |
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63 | =item * How can I get a binary version of Perl? |
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64 | |
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65 | =item * I don't have a C compiler on my system. How can I compile perl? |
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66 | |
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67 | =item * I copied the Perl binary from one machine to another, but scripts don't work. |
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68 | |
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69 | =item * I grabbed the sources and tried to compile but gdbm/dynamic loading/malloc/linking/... failed. How do I make it work? |
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70 | |
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71 | =item * What modules and extensions are available for Perl? What is CPAN? What does CPAN/src/... mean? |
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72 | |
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73 | =item * Is there an ISO or ANSI certified version of Perl? |
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74 | |
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75 | =item * Where can I get information on Perl? |
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76 | |
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77 | =item * What are the Perl newsgroups on USENET? Where do I post questions? |
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78 | |
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79 | =item * Where should I post source code? |
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80 | |
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81 | =item * Perl Books |
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82 | |
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83 | =item * Perl in Magazines |
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84 | |
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85 | =item * Perl on the Net: FTP and WWW Access |
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86 | |
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87 | =item * What mailing lists are there for perl? |
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88 | |
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89 | =item * Archives of comp.lang.perl.misc |
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90 | |
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91 | =item * Where can I buy a commercial version of Perl? |
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92 | |
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93 | =item * Where do I send bug reports? |
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94 | |
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95 | =item * What is perl.com? |
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96 | |
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97 | =back |
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98 | |
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99 | |
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100 | =item L<perlfaq3>: Programming Tools |
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101 | |
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102 | Programmer tools and programming support. |
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103 | |
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104 | =over 4 |
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105 | |
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106 | =item * How do I do (anything)? |
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107 | |
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108 | =item * How can I use Perl interactively? |
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109 | |
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110 | =item * Is there a Perl shell? |
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111 | |
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112 | =item * How do I debug my Perl programs? |
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113 | |
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114 | =item * How do I profile my Perl programs? |
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115 | |
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116 | =item * How do I cross-reference my Perl programs? |
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117 | |
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118 | =item * Is there a pretty-printer (formatter) for Perl? |
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119 | |
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120 | =item * Is there a ctags for Perl? |
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121 | |
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122 | =item * Is there an IDE or Windows Perl Editor? |
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123 | |
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124 | =item * Where can I get Perl macros for vi? |
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125 | |
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126 | =item * Where can I get perl-mode for emacs? |
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127 | |
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128 | =item * How can I use curses with Perl? |
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129 | |
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130 | =item * How can I use X or Tk with Perl? |
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131 | |
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132 | =item * How can I generate simple menus without using CGI or Tk? |
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133 | |
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134 | =item * What is undump? |
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135 | |
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136 | =item * How can I make my Perl program run faster? |
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137 | |
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138 | =item * How can I make my Perl program take less memory? |
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139 | |
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140 | =item * Is it unsafe to return a pointer to local data? |
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141 | |
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142 | =item * How can I free an array or hash so my program shrinks? |
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143 | |
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144 | =item * How can I make my CGI script more efficient? |
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145 | |
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146 | =item * How can I hide the source for my Perl program? |
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147 | |
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148 | =item * How can I compile my Perl program into byte code or C? |
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149 | |
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150 | =item * How can I compile Perl into Java? |
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151 | |
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152 | =item * How can I get C<#!perl> to work on [MS-DOS,NT,...]? |
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153 | |
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154 | =item * Can I write useful perl programs on the command line? |
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155 | |
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156 | =item * Why don't perl one-liners work on my DOS/Mac/VMS system? |
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157 | |
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158 | =item * Where can I learn about CGI or Web programming in Perl? |
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159 | |
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160 | =item * Where can I learn about object-oriented Perl programming? |
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161 | |
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162 | =item * Where can I learn about linking C with Perl? [h2xs, xsubpp] |
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163 | |
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164 | =item * I've read perlembed, perlguts, etc., but I can't embed perl in |
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165 | my C program, what am I doing wrong? |
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166 | |
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167 | =item * When I tried to run my script, I got this message. What does it |
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168 | mean? |
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169 | |
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170 | =item * What's MakeMaker? |
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171 | |
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172 | =back |
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173 | |
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174 | |
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175 | =item L<perlfaq4>: Data Manipulation |
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176 | |
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177 | Manipulating numbers, dates, strings, arrays, hashes, and |
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178 | miscellaneous data issues. |
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179 | |
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180 | =over 4 |
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181 | |
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182 | =item * Why am I getting long decimals (eg, 19.9499999999999) instead of the numbers I should be getting (eg, 19.95)? |
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183 | |
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184 | =item * Why isn't my octal data interpreted correctly? |
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185 | |
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186 | =item * Does Perl have a round() function? What about ceil() and floor()? Trig functions? |
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187 | |
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188 | =item * How do I convert bits into ints? |
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189 | |
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190 | =item * Why doesn't & work the way I want it to? |
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191 | |
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192 | =item * How do I multiply matrices? |
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193 | |
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194 | =item * How do I perform an operation on a series of integers? |
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195 | |
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196 | =item * How can I output Roman numerals? |
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197 | |
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198 | =item * Why aren't my random numbers random? |
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199 | |
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200 | =item * How do I find the week-of-the-year/day-of-the-year? |
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201 | |
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202 | =item * How do I find the current century or millennium? |
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203 | |
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204 | =item * How can I compare two dates and find the difference? |
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205 | |
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206 | =item * How can I take a string and turn it into epoch seconds? |
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207 | |
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208 | =item * How can I find the Julian Day? |
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209 | |
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210 | =item * How do I find yesterday's date? |
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211 | |
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212 | =item * Does Perl have a year 2000 problem? Is Perl Y2K compliant? |
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213 | |
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214 | =item * How do I validate input? |
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215 | |
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216 | =item * How do I unescape a string? |
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217 | |
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218 | =item * How do I remove consecutive pairs of characters? |
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219 | |
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220 | =item * How do I expand function calls in a string? |
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221 | |
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222 | =item * How do I find matching/nesting anything? |
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223 | |
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224 | =item * How do I reverse a string? |
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225 | |
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226 | =item * How do I expand tabs in a string? |
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227 | |
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228 | =item * How do I reformat a paragraph? |
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229 | |
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230 | =item * How can I access/change the first N letters of a string? |
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231 | |
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232 | =item * How do I change the Nth occurrence of something? |
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233 | |
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234 | =item * How can I count the number of occurrences of a substring within a string? |
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235 | |
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236 | =item * How do I capitalize all the words on one line? |
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237 | |
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238 | =item * How can I split a [character] delimited string except when inside |
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239 | [character]? (Comma-separated files) |
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240 | |
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241 | =item * How do I strip blank space from the beginning/end of a string? |
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242 | |
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243 | =item * How do I pad a string with blanks or pad a number with zeroes? |
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244 | |
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245 | =item * How do I extract selected columns from a string? |
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246 | |
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247 | =item * How do I find the soundex value of a string? |
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248 | |
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249 | =item * How can I expand variables in text strings? |
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250 | |
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251 | =item * What's wrong with always quoting "$vars"? |
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252 | |
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253 | =item * Why don't my <<HERE documents work? |
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254 | |
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255 | =item * What is the difference between a list and an array? |
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256 | |
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257 | =item * What is the difference between $array[1] and @array[1]? |
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258 | |
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259 | =item * How can I remove duplicate elements from a list or array? |
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260 | |
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261 | =item * How can I tell whether a list or array contains a certain element? |
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262 | |
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263 | =item * How do I compute the difference of two arrays? How do I compute the intersection of two arrays? |
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264 | |
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265 | =item * How do I test whether two arrays or hashes are equal? |
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266 | |
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267 | =item * How do I find the first array element for which a condition is true? |
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268 | |
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269 | =item * How do I handle linked lists? |
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270 | |
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271 | =item * How do I handle circular lists? |
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272 | |
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273 | =item * How do I shuffle an array randomly? |
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274 | |
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275 | =item * How do I process/modify each element of an array? |
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276 | |
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277 | =item * How do I select a random element from an array? |
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278 | |
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279 | =item * How do I permute N elements of a list? |
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280 | |
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281 | =item * How do I sort an array by (anything)? |
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282 | |
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283 | =item * How do I manipulate arrays of bits? |
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284 | |
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285 | =item * Why does defined() return true on empty arrays and hashes? |
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286 | |
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287 | =item * How do I process an entire hash? |
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288 | |
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289 | =item * What happens if I add or remove keys from a hash while iterating over it? |
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290 | |
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291 | =item * How do I look up a hash element by value? |
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292 | |
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293 | =item * How can I know how many entries are in a hash? |
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294 | |
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295 | =item * How do I sort a hash (optionally by value instead of key)? |
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296 | |
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297 | =item * How can I always keep my hash sorted? |
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298 | |
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299 | =item * What's the difference between "delete" and "undef" with hashes? |
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300 | |
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301 | =item * Why don't my tied hashes make the defined/exists distinction? |
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302 | |
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303 | =item * How do I reset an each() operation part-way through? |
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304 | |
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305 | =item * How can I get the unique keys from two hashes? |
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306 | |
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307 | =item * How can I store a multidimensional array in a DBM file? |
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308 | |
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309 | =item * How can I make my hash remember the order I put elements into it? |
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310 | |
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311 | =item * Why does passing a subroutine an undefined element in a hash create it? |
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312 | |
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313 | =item * How can I make the Perl equivalent of a C structure/C++ class/hash or array of hashes or arrays? |
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314 | |
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315 | =item * How can I use a reference as a hash key? |
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316 | |
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317 | =item * How do I handle binary data correctly? |
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318 | |
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319 | =item * How do I determine whether a scalar is a number/whole/integer/float? |
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320 | |
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321 | =item * How do I keep persistent data across program calls? |
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322 | |
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323 | =item * How do I print out or copy a recursive data structure? |
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324 | |
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325 | =item * How do I define methods for every class/object? |
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326 | |
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327 | =item * How do I verify a credit card checksum? |
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328 | |
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329 | =item * How do I pack arrays of doubles or floats for XS code? |
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330 | |
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331 | =back |
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332 | |
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333 | |
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334 | =item L<perlfaq5>: Files and Formats |
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335 | |
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336 | I/O and the "f" issues: filehandles, flushing, formats and footers. |
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337 | |
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338 | =over 4 |
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339 | |
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340 | =item * How do I flush/unbuffer an output filehandle? Why must I do this? |
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341 | |
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342 | =item * How do I change one line in a file/delete a line in a file/insert a line in the middle of a file/append to the beginning of a file? |
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343 | |
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344 | =item * How do I count the number of lines in a file? |
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345 | |
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346 | =item * How do I make a temporary file name? |
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347 | |
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348 | =item * How can I manipulate fixed-record-length files? |
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349 | |
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350 | =item * How can I make a filehandle local to a subroutine? How do I pass filehandles between subroutines? How do I make an array of filehandles? |
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351 | |
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352 | =item * How can I use a filehandle indirectly? |
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353 | |
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354 | =item * How can I set up a footer format to be used with write()? |
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355 | |
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356 | =item * How can I write() into a string? |
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357 | |
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358 | =item * How can I output my numbers with commas added? |
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359 | |
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360 | =item * How can I translate tildes (~) in a filename? |
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361 | |
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362 | =item * How come when I open a file read-write it wipes it out? |
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363 | |
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364 | =item * Why do I sometimes get an "Argument list too long" when I use <*>? |
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365 | |
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366 | =item * Is there a leak/bug in glob()? |
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367 | |
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368 | =item * How can I open a file with a leading ">" or trailing blanks? |
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369 | |
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370 | =item * How can I reliably rename a file? |
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371 | |
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372 | =item * How can I lock a file? |
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373 | |
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374 | =item * Why can't I just open(FH, ">file.lock")? |
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375 | |
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376 | =item * I still don't get locking. I just want to increment the number in the file. How can I do this? |
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377 | |
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378 | =item * How do I randomly update a binary file? |
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379 | |
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380 | =item * How do I get a file's timestamp in perl? |
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381 | |
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382 | =item * How do I set a file's timestamp in perl? |
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383 | |
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384 | =item * How do I print to more than one file at once? |
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385 | |
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386 | =item * How can I read in an entire file all at once? |
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387 | |
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388 | =item * How can I read in a file by paragraphs? |
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389 | |
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390 | =item * How can I read a single character from a file? From the keyboard? |
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391 | |
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392 | =item * How can I tell whether there's a character waiting on a filehandle? |
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393 | |
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394 | =item * How do I do a C<tail -f> in perl? |
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395 | |
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396 | =item * How do I dup() a filehandle in Perl? |
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397 | |
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398 | =item * How do I close a file descriptor by number? |
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399 | |
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400 | =item * Why can't I use "C:\temp\foo" in DOS paths? What doesn't `C:\temp\foo.exe` work? |
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401 | |
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402 | =item * Why doesn't glob("*.*") get all the files? |
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403 | |
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404 | =item * Why does Perl let me delete read-only files? Why does C<-i> clobber protected files? Isn't this a bug in Perl? |
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405 | |
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406 | =item * How do I select a random line from a file? |
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407 | |
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408 | =item * Why do I get weird spaces when I print an array of lines? |
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409 | |
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410 | =back |
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411 | |
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412 | |
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413 | =item L<perlfaq6>: Regexps |
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414 | |
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415 | Pattern matching and regular expressions. |
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416 | |
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417 | =over 4 |
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418 | |
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419 | =item * How can I hope to use regular expressions without creating illegible and unmaintainable code? |
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420 | |
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421 | =item * I'm having trouble matching over more than one line. What's wrong? |
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422 | |
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423 | =item * How can I pull out lines between two patterns that are themselves on different lines? |
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424 | |
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425 | =item * I put a regular expression into $/ but it didn't work. What's wrong? |
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426 | |
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427 | =item * How do I substitute case insensitively on the LHS, but preserving case on the RHS? |
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428 | |
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429 | =item * How can I make C<\w> match national character sets? |
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430 | |
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431 | =item * How can I match a locale-smart version of C</[a-zA-Z]/>? |
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432 | |
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433 | =item * How can I quote a variable to use in a regex? |
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434 | |
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435 | =item * What is C</o> really for? |
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436 | |
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437 | =item * How do I use a regular expression to strip C style comments from a file? |
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438 | |
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439 | =item * Can I use Perl regular expressions to match balanced text? |
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440 | |
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441 | =item * What does it mean that regexes are greedy? How can I get around it? |
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442 | |
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443 | =item * How do I process each word on each line? |
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444 | |
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445 | =item * How can I print out a word-frequency or line-frequency summary? |
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446 | |
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447 | =item * How can I do approximate matching? |
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448 | |
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449 | =item * How do I efficiently match many regular expressions at once? |
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450 | |
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451 | =item * Why don't word-boundary searches with C<\b> work for me? |
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452 | |
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453 | =item * Why does using $&, $`, or $' slow my program down? |
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454 | |
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455 | =item * What good is C<\G> in a regular expression? |
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456 | |
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457 | =item * Are Perl regexes DFAs or NFAs? Are they POSIX compliant? |
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458 | |
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459 | =item * What's wrong with using grep or map in a void context? |
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460 | |
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461 | =item * How can I match strings with multibyte characters? |
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462 | |
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463 | =item * How do I match a pattern that is supplied by the user? |
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464 | |
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465 | =back |
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466 | |
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467 | |
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468 | =item L<perlfaq7>: General Perl Language Issues |
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469 | |
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470 | General Perl language issues that don't clearly fit into any of the |
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471 | other sections. |
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472 | |
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473 | =over 4 |
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474 | |
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475 | =item * Can I get a BNF/yacc/RE for the Perl language? |
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476 | |
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477 | =item * What are all these $@%&* punctuation signs, and how do I know when to use them? |
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478 | |
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479 | =item * Do I always/never have to quote my strings or use semicolons and commas? |
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480 | |
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481 | =item * How do I skip some return values? |
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482 | |
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483 | =item * How do I temporarily block warnings? |
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484 | |
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485 | =item * What's an extension? |
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486 | |
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487 | =item * Why do Perl operators have different precedence than C operators? |
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488 | |
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489 | =item * How do I declare/create a structure? |
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490 | |
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491 | =item * How do I create a module? |
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492 | |
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493 | =item * How do I create a class? |
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494 | |
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495 | =item * How can I tell if a variable is tainted? |
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496 | |
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497 | =item * What's a closure? |
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498 | |
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499 | =item * What is variable suicide and how can I prevent it? |
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500 | |
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501 | =item * How can I pass/return a {Function, FileHandle, Array, Hash, Method, Regex}? |
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502 | |
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503 | =item * How do I create a static variable? |
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504 | |
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505 | =item * What's the difference between dynamic and lexical (static) scoping? Between local() and my()? |
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506 | |
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507 | =item * How can I access a dynamic variable while a similarly named lexical is in scope? |
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508 | |
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509 | =item * What's the difference between deep and shallow binding? |
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510 | |
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511 | =item * Why doesn't "my($foo) = <FILE>;" work right? |
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512 | |
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513 | =item * How do I redefine a builtin function, operator, or method? |
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514 | |
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515 | =item * What's the difference between calling a function as &foo and foo()? |
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516 | |
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517 | =item * How do I create a switch or case statement? |
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518 | |
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519 | =item * How can I catch accesses to undefined variables/functions/methods? |
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520 | |
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521 | =item * Why can't a method included in this same file be found? |
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522 | |
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523 | =item * How can I find out my current package? |
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524 | |
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525 | =item * How can I comment out a large block of perl code? |
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526 | |
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527 | =item * How do I clear a package? |
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528 | |
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529 | =item * How can I use a variable as a variable name? |
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530 | |
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531 | =back |
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532 | |
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533 | |
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534 | =item L<perlfaq8>: System Interaction |
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535 | |
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536 | Interprocess communication (IPC), control over the user-interface |
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537 | (keyboard, screen and pointing devices). |
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538 | |
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539 | =over 4 |
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540 | |
---|
541 | =item * How do I find out which operating system I'm running under? |
---|
542 | |
---|
543 | =item * How come exec() doesn't return? |
---|
544 | |
---|
545 | =item * How do I do fancy stuff with the keyboard/screen/mouse? |
---|
546 | |
---|
547 | =item * How do I print something out in color? |
---|
548 | |
---|
549 | =item * How do I read just one key without waiting for a return key? |
---|
550 | |
---|
551 | =item * How do I check whether input is ready on the keyboard? |
---|
552 | |
---|
553 | =item * How do I clear the screen? |
---|
554 | |
---|
555 | =item * How do I get the screen size? |
---|
556 | |
---|
557 | =item * How do I ask the user for a password? |
---|
558 | |
---|
559 | =item * How do I read and write the serial port? |
---|
560 | |
---|
561 | =item * How do I decode encrypted password files? |
---|
562 | |
---|
563 | =item * How do I start a process in the background? |
---|
564 | |
---|
565 | =item * How do I trap control characters/signals? |
---|
566 | |
---|
567 | =item * How do I modify the shadow password file on a Unix system? |
---|
568 | |
---|
569 | =item * How do I set the time and date? |
---|
570 | |
---|
571 | =item * How can I sleep() or alarm() for under a second? |
---|
572 | |
---|
573 | =item * How can I measure time under a second? |
---|
574 | |
---|
575 | =item * How can I do an atexit() or setjmp()/longjmp()? (Exception handling) |
---|
576 | |
---|
577 | =item * Why doesn't my sockets program work under System V (Solaris)? What does the error message "Protocol not supported" mean? |
---|
578 | |
---|
579 | =item * How can I call my system's unique C functions from Perl? |
---|
580 | |
---|
581 | =item * Where do I get the include files to do ioctl() or syscall()? |
---|
582 | |
---|
583 | =item * Why do setuid perl scripts complain about kernel problems? |
---|
584 | |
---|
585 | =item * How can I open a pipe both to and from a command? |
---|
586 | |
---|
587 | =item * Why can't I get the output of a command with system()? |
---|
588 | |
---|
589 | =item * How can I capture STDERR from an external command? |
---|
590 | |
---|
591 | =item * Why doesn't open() return an error when a pipe open fails? |
---|
592 | |
---|
593 | =item * What's wrong with using backticks in a void context? |
---|
594 | |
---|
595 | =item * How can I call backticks without shell processing? |
---|
596 | |
---|
597 | =item * Why can't my script read from STDIN after I gave it EOF (^D on Unix, ^Z on MS-DOS)? |
---|
598 | |
---|
599 | =item * How can I convert my shell script to perl? |
---|
600 | |
---|
601 | =item * Can I use perl to run a telnet or ftp session? |
---|
602 | |
---|
603 | =item * How can I write expect in Perl? |
---|
604 | |
---|
605 | =item * Is there a way to hide perl's command line from programs such as "ps"? |
---|
606 | |
---|
607 | =item * I {changed directory, modified my environment} in a perl script. How come the change disappeared when I exited the script? How do I get my changes to be visible? |
---|
608 | |
---|
609 | =item * How do I close a process's filehandle without waiting for it to complete? |
---|
610 | |
---|
611 | =item * How do I fork a daemon process? |
---|
612 | |
---|
613 | =item * How do I make my program run with sh and csh? |
---|
614 | |
---|
615 | =item * How do I find out if I'm running interactively or not? |
---|
616 | |
---|
617 | =item * How do I timeout a slow event? |
---|
618 | |
---|
619 | =item * How do I set CPU limits? |
---|
620 | |
---|
621 | =item * How do I avoid zombies on a Unix system? |
---|
622 | |
---|
623 | =item * How do I use an SQL database? |
---|
624 | |
---|
625 | =item * How do I make a system() exit on control-C? |
---|
626 | |
---|
627 | =item * How do I open a file without blocking? |
---|
628 | |
---|
629 | =item * How do I install a module from CPAN? |
---|
630 | |
---|
631 | =item * What's the difference between require and use? |
---|
632 | |
---|
633 | =item * How do I keep my own module/library directory? |
---|
634 | |
---|
635 | =item * How do I add the directory my program lives in to the module/library search path? |
---|
636 | |
---|
637 | =item * How do I add a directory to my include path at runtime? |
---|
638 | |
---|
639 | =item * What is socket.ph and where do I get it? |
---|
640 | |
---|
641 | =back |
---|
642 | |
---|
643 | |
---|
644 | =item L<perlfaq9>: Networking |
---|
645 | |
---|
646 | Networking, the Internet, and a few on the web. |
---|
647 | |
---|
648 | =over 4 |
---|
649 | |
---|
650 | =item * My CGI script runs from the command line but not the browser. (500 Server Error) |
---|
651 | |
---|
652 | =item * How can I get better error messages from a CGI program? |
---|
653 | |
---|
654 | =item * How do I remove HTML from a string? |
---|
655 | |
---|
656 | =item * How do I extract URLs? |
---|
657 | |
---|
658 | =item * How do I download a file from the user's machine? How do I open a file on another machine? |
---|
659 | |
---|
660 | =item * How do I make a pop-up menu in HTML? |
---|
661 | |
---|
662 | =item * How do I fetch an HTML file? |
---|
663 | |
---|
664 | =item * How do I automate an HTML form submission? |
---|
665 | |
---|
666 | =item * How do I decode or create those %-encodings on the web? |
---|
667 | |
---|
668 | =item * How do I redirect to another page? |
---|
669 | |
---|
670 | =item * How do I put a password on my web pages? |
---|
671 | |
---|
672 | =item * How do I edit my .htpasswd and .htgroup files with Perl? |
---|
673 | |
---|
674 | =item * How do I make sure users can't enter values into a form that cause my CGI script to do bad things? |
---|
675 | |
---|
676 | =item * How do I parse a mail header? |
---|
677 | |
---|
678 | =item * How do I decode a CGI form? |
---|
679 | |
---|
680 | =item * How do I check a valid mail address? |
---|
681 | |
---|
682 | =item * How do I decode a MIME/BASE64 string? |
---|
683 | |
---|
684 | =item * How do I return the user's mail address? |
---|
685 | |
---|
686 | =item * How do I send mail? |
---|
687 | |
---|
688 | =item * How do I read mail? |
---|
689 | |
---|
690 | =item * How do I find out my hostname/domainname/IP address? |
---|
691 | |
---|
692 | =item * How do I fetch a news article or the active newsgroups? |
---|
693 | |
---|
694 | =item * How do I fetch/put an FTP file? |
---|
695 | |
---|
696 | =item * How can I do RPC in Perl? |
---|
697 | |
---|
698 | =back |
---|
699 | |
---|
700 | |
---|
701 | =back |
---|
702 | |
---|
703 | =head2 Where to get this document |
---|
704 | |
---|
705 | This document is posted regularly to comp.lang.perl.announce and |
---|
706 | several other related newsgroups. It is available in a variety of |
---|
707 | formats from CPAN in the /CPAN/doc/FAQs/FAQ/ directory, or on the web |
---|
708 | at http://www.perl.com/perl/faq/ . |
---|
709 | |
---|
710 | =head2 How to contribute to this document |
---|
711 | |
---|
712 | You may mail corrections, additions, and suggestions to |
---|
713 | perlfaq-suggestions@perl.com . This alias should not be |
---|
714 | used to I<ask> FAQs. It's for fixing the current FAQ. |
---|
715 | Send questions to the comp.lang.perl.misc newsgroup. |
---|
716 | |
---|
717 | =head2 What will happen if you mail your Perl programming problems to the authors |
---|
718 | |
---|
719 | Your questions will probably go unread, unless they're suggestions of |
---|
720 | new questions to add to the FAQ, in which case they should have gone |
---|
721 | to the perlfaq-suggestions@perl.com instead. |
---|
722 | |
---|
723 | You should have read section 2 of this faq. There you would have |
---|
724 | learned that comp.lang.perl.misc is the appropriate place to go for |
---|
725 | free advice. If your question is really important and you require a |
---|
726 | prompt and correct answer, you should hire a consultant. |
---|
727 | |
---|
728 | =head1 Credits |
---|
729 | |
---|
730 | When I first began the Perl FAQ in the late 80s, I never realized it |
---|
731 | would have grown to over a hundred pages, nor that Perl would ever become |
---|
732 | so popular and widespread. This document could not have been written |
---|
733 | without the tremendous help provided by Larry Wall and the rest of the |
---|
734 | Perl Porters. |
---|
735 | |
---|
736 | =head1 Author and Copyright Information |
---|
737 | |
---|
738 | Copyright (c) 1997-1999 Tom Christiansen and Nathan Torkington. |
---|
739 | All rights reserved. |
---|
740 | |
---|
741 | =head2 Bundled Distributions |
---|
742 | |
---|
743 | When included as part of the Standard Version of Perl, or as part of |
---|
744 | its complete documentation whether printed or otherwise, this work |
---|
745 | may be distributed only under the terms of Perl's Artistic License. |
---|
746 | Any distribution of this file or derivatives thereof I<outside> |
---|
747 | of that package require that special arrangements be made with |
---|
748 | copyright holder. |
---|
749 | |
---|
750 | Irrespective of its distribution, all code examples in these files |
---|
751 | are hereby placed into the public domain. You are permitted and |
---|
752 | encouraged to use this code in your own programs for fun |
---|
753 | or for profit as you see fit. A simple comment in the code giving |
---|
754 | credit would be courteous but is not required. |
---|
755 | |
---|
756 | =head2 Disclaimer |
---|
757 | |
---|
758 | This information is offered in good faith and in the hope that it may |
---|
759 | be of use, but is not guaranteed to be correct, up to date, or suitable |
---|
760 | for any particular purpose whatsoever. The authors accept no liability |
---|
761 | in respect of this information or its use. |
---|
762 | |
---|
763 | =head1 Changes |
---|
764 | |
---|
765 | =over 4 |
---|
766 | |
---|
767 | =item 23/May/99 |
---|
768 | |
---|
769 | Extensive updates from the net in preparation for 5.6 release. |
---|
770 | |
---|
771 | =item 13/April/99 |
---|
772 | |
---|
773 | More minor touch-ups. Added new question at the end |
---|
774 | of perlfaq7 on variable names within variables. |
---|
775 | |
---|
776 | =item 7/January/99 |
---|
777 | |
---|
778 | Small touchups here and there. Added all questions in this |
---|
779 | document as a sort of table of contents. |
---|
780 | |
---|
781 | =item 22/June/98 |
---|
782 | |
---|
783 | Significant changes throughout in preparation for the 5.005 |
---|
784 | release. |
---|
785 | |
---|
786 | =item 24/April/97 |
---|
787 | |
---|
788 | Style and whitespace changes from Chip, new question on reading one |
---|
789 | character at a time from a terminal using POSIX from Tom. |
---|
790 | |
---|
791 | =item 23/April/97 |
---|
792 | |
---|
793 | Added http://www.oasis.leo.org/perl/ to L<perlfaq2>. Style fix to |
---|
794 | L<perlfaq3>. Added floating point precision, fixed complex number |
---|
795 | arithmetic, cross-references, caveat for Text::Wrap, alternative |
---|
796 | answer for initial capitalizing, fixed incorrect regexp, added example |
---|
797 | of Tie::IxHash to L<perlfaq4>. Added example of passing and storing |
---|
798 | filehandles, added commify to L<perlfaq5>. Restored variable suicide, |
---|
799 | and added mass commenting to L<perlfaq7>. Added Net::Telnet, fixed |
---|
800 | backticks, added reader/writer pair to telnet question, added FindBin, |
---|
801 | grouped module questions together in L<perlfaq8>. Expanded caveats |
---|
802 | for the simple URL extractor, gave LWP example, added CGI security |
---|
803 | question, expanded on the mail address answer in L<perlfaq9>. |
---|
804 | |
---|
805 | =item 25/March/97 |
---|
806 | |
---|
807 | Added more info to the binary distribution section of L<perlfaq2>. |
---|
808 | Added Net::Telnet to L<perlfaq6>. Fixed typos in L<perlfaq8>. Added |
---|
809 | mail sending example to L<perlfaq9>. Added Merlyn's columns to |
---|
810 | L<perlfaq2>. |
---|
811 | |
---|
812 | =item 18/March/97 |
---|
813 | |
---|
814 | Added the DATE to the NAME section, indicating which sections have |
---|
815 | changed. |
---|
816 | |
---|
817 | Mentioned SIGPIPE and L<perlipc> in the forking open answer in |
---|
818 | L<perlfaq8>. |
---|
819 | |
---|
820 | Fixed description of a regular expression in L<perlfaq4>. |
---|
821 | |
---|
822 | =item 17/March/97 Version |
---|
823 | |
---|
824 | Various typos fixed throughout. |
---|
825 | |
---|
826 | Added new question on Perl BNF on L<perlfaq7>. |
---|
827 | |
---|
828 | =item Initial Release: 11/March/97 |
---|
829 | |
---|
830 | This is the initial release of version 3 of the FAQ; consequently there |
---|
831 | have been no changes since its initial release. |
---|
832 | |
---|
833 | =back |
---|