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1 .ps 11
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2 .ce
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3 Seminar ``Software Analysis''
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4 .TL
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5 \fR\s-6Why\s0\fP
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6 .br
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7 the Unix Philosophy
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8 .br
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9 .vs -4
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10 \fR\s-6still matters\s0\fP
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11 .AU
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12 .ft R
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13 .sp .5i
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14 .sp .5i
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15 .ps 11
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16 markus schnalke <meillo@marmaro.de>
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17
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18
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58
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19
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20 .S "Software design
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21 .rs
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22 .sp
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23 .LP
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24 \&... is about quality
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25 .I
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26 Good design \(-> good quality
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27 .I
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28 Bad design \(-> problems
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29 .sp
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30 .LP
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31 \&... and consistency
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32 .LP
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33 .sp 2
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34 Unix Phil = guidelines for good design
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35
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36
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37
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38 .S "Unix Phil and Software dev processes
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39 .rs
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40 .sp
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41 .LP
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42 The Unix Phil:
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43 .I
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44 mostly *what*
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45 .sp
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46 .LP
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47 Software dev processes:
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48 .I
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49 mostly *how*
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50 .sp 2
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51 .LP
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52 Extreme Programming and the Unix Phil
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53 are good friends
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54
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55
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56
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56
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57 .S "The Unix Phil *itself*
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58 .rs
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59 .sp
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60 .LP
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61 Wikipedia:
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62 .ce 99
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63 .sp
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64 The Unix philosophy is
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65 a set of cultural norms and philosophical approaches
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66 to developing software
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67 based on the experience
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68 of leading developers of the Unix operating system.
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69 .sp
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70
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71
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72
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73 .S Motivation
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74 .rs
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75 .sp
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76 .LP
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58
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77 .ce
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78 Write the best possible programs for yourself
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79 .sp 3
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80 .LP
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81 .ce
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82 Avoid \fBcomplexity\fP first and foremost!
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83 .LP
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84 .ce
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85 Exploit software \fBleverage\fP!
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86
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87
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88
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89 .S "The Unix Phil by Doug McIlroy (1978)
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90 .rs
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91 .sp
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92 .LP
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93 This is the Unix philosophy:
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94 .I
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95 Write programs that do one thing and do it well.
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96 .I
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97 Write programs to work together.
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98 .I
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99 Write programs to handle text streams, because that is a universal interface.
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100
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101
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102
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103 .S "The Unix Phil by Mike Gancarz (1995)
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104 .rs
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105 .sp .2v
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106 .I
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107 Small is beautiful.
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108 .I
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109 Make each program do one thing well.
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110 .I
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111 Build a prototype as soon as possible.
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112 .I
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113 Choose portability over efficiency.
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114 .I
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115 Store data in flat text files.
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116 .I
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117 Use software leverage to your advantage.
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118 .I
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119 Use shell scripts to increase leverage and portability.
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120 .I
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121 Avoid captive user interfaces.
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122 .I
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123 Make every program a filter.
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124 .sp 1
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125 .LP
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126 Plus ten lesser tenets
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127
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128
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129
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130 .S "Case studies
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131 .LP
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132 .B "MH / nmh
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133 .LP
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134 The only MUA that is a toolchest
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135 .LP
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136 Makes use of the powerful shell
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137 .LP
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138 Great example of applied Unix Phil
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139 .sp
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140 .LP
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141 .B uzbl
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142 .LP
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143 A web browser that adheres to the Unix Phil
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144 .LP
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145 Central question:
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146 .br
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147 What is the one thing a web browser should do well?
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148 .LP
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149 Makes very visible use of software leverage
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150
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151
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152
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153 .S "Why?
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154 .rs
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155 .sp
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156 .LP
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157 .ce
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158 We don't need just any solutions, we need good ones
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159 .sp 3
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160 .LP
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161 .ce
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162 \fBComplexity\fP is the ``boss enemy'' of software developers
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163 .LP
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164 .ce
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165 \fBLeverage\fP is the largest unique benefit of software
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166
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167
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168
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169 .S "Further reading
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170 .LP
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171 The paper to the slides
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172 .sp
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173 .LP
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174 My talk on this topic at the ChaosSeminar of CCC Ulm
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175 .CW \s-2http://ulm.ccc.de/ChaosSeminar/2010/03_UnixPhil\s0
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176 .sp
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177 .LP
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178 Mike Gancarz' book
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179 \fI``The Unix Philosophy''\fP
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180 .sp
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181 .LP
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182 \fI``cat -v Considered Harmful''\fP
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183 by Pike and Kernighan
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184 .CW \s-2http://harmful.cat-v.org/cat-v/\s+2
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185
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186
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187
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188 .S Colophon
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189 .LP
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190 The paper and slides were prepared with:
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191 .br
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192 .CW "vi sed awk refer troff dpost spell make hg
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193 .sp
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194 .LP
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195 Most of the tools are from
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196 .CW \s-2http://heirloom.sf.net\s0
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197 .LP
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198 The `slides' macros are based on
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199 .br
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200 .CW \s-2http://repo.cat-v.org/troff-slider/\s0
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201 .sp 2
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202 .LP
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203 The paper, the slides, and the complete sources are available on my website
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204 .CW \s-2http://marmaro.de/docs\s+2
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205 .sp 3
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206 2010-04-16
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