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1 .if n .pl 1000i
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2 .de XX
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3 .pl 1v
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4 ..
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5 .em XX
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6 .\".nr PI 0
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7 .\".if t .nr PD .5v
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8 .\".if n .nr PD 1v
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9 .nr lu 0
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10 .de CW
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11 .nr PQ \\n(.f
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meillo@0
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12 .if t .ft CW
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13 .ie \\$1 .if n .ul 999
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14 .el .if n .ul 1
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15 .if t .if !\\$1 \&\\$1\f\\n(PQ\\$2
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16 .if n .if \\n(.$=1 \&\\$1
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17 .if n .if \\n(.$>1 \&\\$1\c
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18 .if n .if \\n(.$>1 \&\\$2
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19 ..
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20 .ds [. \ [
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21 .ds .] ]
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meillo@1
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22 .\"----------------------------------------
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meillo@0
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23 .TL
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24 Why the Unix Philosophy matters
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25 .AU
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26 markus schnalke <meillo@marmaro.de>
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27 .AI
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28 .ce 0
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29 University Ulm
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30 .AB
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31 .ti \n(.iu
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32 This term paper discusses the importance of the Unix Philosophy in software design.
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33 Today, few software designers are aware of these concepts,
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34 and thus most modern software is limited and does not use software leverage.
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35 Knowing and following the tenets of the Unix Philosophy makes software more valuable.
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meillo@0
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36 .AE
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37
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38 .2C
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39 .NH 1
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meillo@0
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40 Introduction
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41 .LP
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meillo@0
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42 Building a software is a process from an idea of the purpose of the software
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43 to the finished program.
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44 No matter \fIhow\fP the process is run, two things are common:
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45 the initial idea and the release.
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46 But the the process inbetween can be of any shape.
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47 The time of release and the maintainance work after the release are ignored here, for the moment.
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48 .PP
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49 The process of building splits mainly in two parts:
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50 the planning of what and how to build, and implementing the plan by writing code.
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51 This paper focuses on the planning \(en the design \(en of software.
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52 The here discussed ideas may be applied to any development process.
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53 Though the Unix Philosphy does recommend how the software development process should look like,
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54 this shall not be of matter here.
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55 Similar, the question of how to write the code is out of focus.
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56 .PP
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57 This paper discusses the connection between software design and the Unix Philosphy.
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58 Software design is the work between the requirements and the plan of how the internals and externals
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59 of the software should look like.
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60 However, the term ``Unix Philosophy'' was used but not explained yet.
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61 .PP
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62 The Unix Philosophy is the essence of how the Unix operating system and its toolchest was designed.
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63 It is no limited set of rules, but what people see what is common to typical Unix software.
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64 Several people stated their view on the Unix Philosophy.
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65 Best known are:
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66 .IP \(bu
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67 Doug McIlroy's summary: ``Write programs that do one thing and do it well.''
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68 .[
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meillo@1
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69 %A M. D. McIlroy
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meillo@1
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70 %A E. N. Pinson
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meillo@1
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71 %A B. A. Taque
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meillo@1
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72 %T UNIX Time-Sharing System Forward
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meillo@1
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73 %J The Bell System Technical Journal
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meillo@1
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74 %D 1978
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75 %V 57
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76 %N 6
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77 %P 1902
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78 .]
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79 .IP \(bu
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80 Mike Gancarz' book ``The UNIX Philosophy''.
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81 .[
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82 %A Mike Gancarz
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83 %T The UNIX Philosophy
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84 %D 1995
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85 %I Digital Press
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86 .]
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meillo@1
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87 .IP \(bu
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88 Eric S. Raymond's book ``The Art of UNIX Programming''.
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89 .[
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90 %A Eric S. Raymond
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91 %T The Art of UNIX Programming
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92 %D 2003
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93 %I Addison-Wesley
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94 %O .CW \s-2http://www.faqs.org/docs/artu/
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95 .]
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96 .LP
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97 These different views on the Unix Philosophy have much in common.
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98 Especially, the main concepts are seen by all of them.
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99 But there are also points on which they differ.
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100 This only underlines what the Unix Philosophy is:
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101 A retrospective view on the main concepts of Unix software;
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102 especially those that were sucessful and unique to Unix.
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103 .PP
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104 Before we will have a look at concrete concepts,
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105 we discuss why software design is important
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106 and what problems bad design introduces.
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107
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108
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109 .NH 1
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110 Importance of software design
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111 .LP
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112 why design at all
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113
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114 - for dev mainly: extendability and maintainability
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115
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116 - for users: usability and flexibility (but you need to learn how to use it)
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117
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118 no design and bad design limit the use of software
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119
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120 .NH 2
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121 Architecture
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122 .LP
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123 the most important design decision.
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124
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125 the topic here
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126
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127 .NH 1
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128 The Unix Philosophy
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129
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130 .NH 2
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131 what it is
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132 .LP
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133 definitions by McIlroy, Gancarz, ESR (maybe already in the intro)
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134 .LP
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135 cf. unix tool chain
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136 .LP
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137 enabler pipe
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138
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139 .NH 2
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140 Interface architecture
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141 .LP
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142 standalone vs. tool chain
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143 .LP
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144 software leverage
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145 .LP
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146 possiblities
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147
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148 .NH 2
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149 Results
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150 .LP
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151 The unix phil is an answer to the sw design question
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152 .LP
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153 tool chains empower the uses of sw
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154
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155 .NH 1
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156 Case study: nmh
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157
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158 .NH 2
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159 History
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meillo@0
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160 .LP
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161 MH, nmh.
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162 They are old.
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163
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164 .NH 2
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165 Contrasts to similar sw
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166 .LP
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167 vs. Thunderbird, mutt, mailx, pine
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168 .LP
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169 flexibility, no redundancy, use the shell
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170
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171 .NH 2
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meillo@0
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172 Gains of the design
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173 .LP
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174
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175 .NH 2
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176 Problems
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177 .LP
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178
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179 .NH 1
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meillo@0
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180 Case study: uzbl
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181
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182 .NH 2
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183 History
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184 .LP
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185 uzbl is young
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186
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187 .NH 2
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188 Contrasts to similar sw
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189 .LP
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190 like with nmh
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191 .LP
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meillo@0
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192 addons, plugins, modules
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193
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194 .NH 2
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195 Gains of the design
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196 .LP
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197
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198 .NH 2
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199 Problems
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200 .LP
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201 broken web
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202
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203 .NH 1
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204 Final thoughts
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205
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206 .NH 2
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207 Quick summary
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208 .LP
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209 good design
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210 .LP
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211 unix phil
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212 .LP
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213 case studies
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214
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215 .NH 2
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216 Why people should choose
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217 .LP
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218 Make the right choice!
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219
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220 .nr PI .5i
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221 .rm ]<
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222 .de ]<
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223 .LP
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224 .de FP
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225 .IP \\\\$1.
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226 \\..
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227 .rm FS FE
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228 ..
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229 .SH
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230 References
|
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231 .[
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232 $LIST$
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233 .]
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234 .wh -1p
|