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<!doctypehtml><html class="sidebar-visible no-js light"lang=en><head><meta charset=UTF-8><title>join - CLI text processing with GNU Coreutils</title><meta content="text/html; charset=utf-8"http-equiv=Content-Type><meta content="Example based guide for specialized text processing with GNU Coreutils"name=description><meta content=width=device-width,initial-scale=1 name=viewport><meta content=#ffffff name=theme-color><meta content="CLI text processing with GNU Coreutils"property=og:title><meta content=website property=og:type><meta content="Example based guide for specialized text processing with GNU Coreutils"property=og:description><meta content=https://learnbyexample.github.io/cli_text_processing_coreutils/ property=og:url><meta content=https://raw.githubusercontent.com/learnbyexample/cli_text_processing_coreutils/main/images/cli_coreutils_ls.png property=og:image><meta content=1280 property=og:image:width><meta content=720 property=og:image:height><meta content=summary_large_image property=twitter:card><meta content=@learn_byexample property=twitter:site><link href=favicon.svg rel=icon><link rel="shortcut icon"href=favicon.png><link href=css/variables.css rel=stylesheet><link href=css/general.css rel=stylesheet><link href=css/chrome.css rel=stylesheet><link href=FontAwesome/css/font-awesome.css rel=stylesheet><link href=fonts/fonts.css rel=stylesheet><link href=highlight.css rel=stylesheet><link href=tomorrow-night.css rel=stylesheet><link href=ayu-highlight.css rel=stylesheet><link href=style.css rel=stylesheet><body><script>var path_to_root = "";
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html.classList.add("sidebar-" + sidebar);</script><nav aria-label="Table of contents"class=sidebar id=sidebar><div class=sidebar-scrollbox><ol class=chapter><li class="chapter-item expanded affix"><a href=cover.html>Cover</a><li class="chapter-item expanded affix"><a href=buy.html>Buy PDF/EPUB versions</a><li class="chapter-item expanded affix"><a href=preface.html>Preface</a><li class="chapter-item expanded"><a href=introduction.html><strong aria-hidden=true>1.</strong> Introduction</a><li class="chapter-item expanded"><a href=cat-tac.html><strong aria-hidden=true>2.</strong> cat and tac</a><li class="chapter-item expanded"><a href=head-tail.html><strong aria-hidden=true>3.</strong> head and tail</a><li class="chapter-item expanded"><a href=tr.html><strong aria-hidden=true>4.</strong> tr</a><li class="chapter-item expanded"><a href=cut.html><strong aria-hidden=true>5.</strong> cut</a><li class="chapter-item expanded"><a href=seq.html><strong aria-hidden=true>6.</strong> seq</a><li class="chapter-item expanded"><a href=shuf.html><strong aria-hidden=true>7.</strong> shuf</a><li class="chapter-item expanded"><a href=paste.html><strong aria-hidden=true>8.</strong> paste</a><li class="chapter-item expanded"><a href=pr.html><strong aria-hidden=true>9.</strong> pr</a><li class="chapter-item expanded"><a href=fold-fmt.html><strong aria-hidden=true>10.</strong> fold and fmt</a><li class="chapter-item expanded"><a href=sort.html><strong aria-hidden=true>11.</strong> sort</a><li class="chapter-item expanded"><a href=uniq.html><strong aria-hidden=true>12.</strong> uniq</a><li class="chapter-item expanded"><a href=comm.html><strong aria-hidden=true>13.</strong> comm</a><li class="chapter-item expanded"><a class=active href=join.html><strong aria-hidden=true>14.</strong> join</a><li class="chapter-item expanded"><a href=nl.html><strong aria-hidden=true>15.</strong> nl</a><li class="chapter-item expanded"><a href=wc.html><strong aria-hidden=true>16.</strong> wc</a><li class="chapter-item expanded"><a href=split.html><strong aria-hidden=true>17.</strong> split</a><li class="chapter-item expanded"><a href=csplit.html><strong aria-hidden=true>18.</strong> csplit</a><li class="chapter-item expanded"><a href=expand-unexpand.html><strong aria-hidden=true>19.</strong> expand and unexpand</a><li class="chapter-item expanded"><a href=basename-dirname.html><strong aria-hidden=true>20.</strong> basename and dirname</a><li class="chapter-item expanded affix"><a href=what_next.html>What next?</a><li class="chapter-item expanded affix"><a href=Exercise_solutions.html>Exercise solutions</a></li><br><hr><li class="chapter-item expanded"><i class="fa fa-github"id=git-repository-button></i><a href=https://github.com/learnbyexample/cli_text_processing_coreutils> Source code</a><li class="chapter-item expanded"><i class="fa fa-home"id=home-button></i><a href=https://learnbyexample.github.io/> My Blog</a><li class="chapter-item expanded"><i class="fa fa-book"id=book-button></i><a href=https://learnbyexample.github.io/books/> My Books</a><li class="chapter-item expanded"><i class="fa fa-envelope"id=mail-button></i><a href=https://learnbyexample.gumroad.com/l/learnbyexample-weekly> learnbyexample weekly</a><li class="chapter-item expanded"><i class="fa fa-twitter"id=twitter-button></i><a href=https://twitter.com/learn_byexample> Twitter</a></ol></div><div class=sidebar-resize-handle id=sidebar-resize-handle></div></nav><div class=page-wrapper id=page-wrapper><div class=page><div id=menu-bar-hover-placeholder></div><div class="menu-bar sticky bordered"id=menu-bar><div class=left-buttons><button aria-label="Toggle Table of Contents"title="Toggle Table of Contents"aria-controls=sidebar class=icon-button id=sidebar-toggle type=button><i class="fa fa-bars"></i></button><button aria-label="Change theme"title="Change theme"aria-controls=theme-list aria-expanded=false aria-haspopup=true class=icon-button id=theme-toggle type=button><i class="fa fa-paint-brush"></i></button><ul aria-label=Themes class=theme-popup id=theme-list role=menu><li role=none><button class=theme id=light role=menuitem>Light (default)</button><li role=none><button class=theme id=rust role=menuitem>Rust</button><li role=none><button class=theme id=coal role=menuitem>Coal</button><li role=none><button class=theme id=navy role=menuitem>Navy</button><li role=none><button class=theme id=ayu role=menuitem>Ayu</button></ul><button aria-label="Toggle Searchbar"title="Search. (Shortkey: s)"aria-controls=searchbar aria-expanded=false aria-keyshortcuts=S class=icon-button id=search-toggle type=button><i class="fa fa-search"></i></button></div><h1 class=menu-title>CLI text processing with GNU Coreutils</h1><div class=right-buttons><a aria-label=Blog href=https://learnbyexample.github.io title=Blog> <i class="fa fa-home"id=home-button></i> </a><a aria-label=Twitter href=https://twitter.com/learn_byexample title=Twitter> <i class="fa fa-twitter"id=twitter-button></i> </a><a aria-label="Git repository"title="Git repository"href=https://github.com/learnbyexample/cli_text_processing_coreutils> <i class="fa fa-github"id=git-repository-button></i> </a></div></div><div class=hidden id=search-wrapper><form class=searchbar-outer id=searchbar-outer><input placeholder="Search this book ..."aria-controls=searchresults-outer aria-describedby=searchresults-header id=searchbar name=searchbar type=search></form><div class="searchresults-outer hidden"id=searchresults-outer><div class=searchresults-header id=searchresults-header></div><ul id=searchresults></ul></div></div><script>document.getElementById('sidebar-toggle').setAttribute('aria-expanded', sidebar === 'visible');
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});</script><div class=content id=content><main><div class=sidetoc><nav class=pagetoc></nav></div><h1 id=join><a class=header href=#join>join</a></h1><p>The <code>join</code> command helps you to combine lines from two files based on a common field. This works best when the input is already sorted by that field.<h2 id=default-join><a class=header href=#default-join>Default join</a></h2><p>By default, <code>join</code> combines two files based on the first field content (also referred as <strong>key</strong>). Only the lines with common keys will be part of the output.<p>The key field will be displayed first in the output (this distinction will come into play if the first field isn't the key). Rest of the line will have the remaining fields from the first and second files, in that order. One or more blanks (space or tab) will be considered as the input field separator and a single space will be used as the output field separator. If present, blank characters at the start of the input lines will be ignored.<pre><code class=language-bash># sample sorted input files
$ cat shopping_jan.txt
apple 10
banana 20
soap 3
tshirt 3
$ cat shopping_feb.txt
banana 15
fig 100
pen 2
soap 1
# combine common lines based on the first field
$ join shopping_jan.txt shopping_feb.txt
banana 20 15
soap 3 1
</code></pre><p>If a field value is present multiple times in the same input file, all possible combinations will be present in the output. As shown below, <code>join</code> will also ensure to add a final newline character even if it wasn't present in the input.<pre><code class=language-bash>$ join <(printf 'a f1_x\na f1_y') <(printf 'a f2_x\na f2_y')
a f1_x f2_x
a f1_x f2_y
a f1_y f2_x
a f1_y f2_y
</code></pre><blockquote><p><img alt=info src=./images/info.svg> Note that the collating order used for <code>join</code> should be same as the one used to <code>sort</code> the input files. Use <code>join -i</code> to ignore case, similar to <code>sort -f</code> usage.</blockquote><blockquote><p><img alt=info src=./images/info.svg> If the input files are not sorted, <code>join</code> will produce an error if there are unpairable lines. You can use the <code>--nocheck-order</code> option to ignore this error. However, as per the documentation, this option "is not guaranteed to produce any particular output."</blockquote><h2 id=non-matching-lines><a class=header href=#non-matching-lines>Non-matching lines</a></h2><p>By default, only the lines having common keys are part of the output. You can use the <code>-a</code> option to also include the non-matching lines from the input files. Use <code>1</code> and <code>2</code> as the argument for the first and second file respectively. You'll later see how to fill missing fields with a custom string.<pre><code class=language-bash># includes non-matching lines from the first file
$ join -a1 shopping_jan.txt shopping_feb.txt
apple 10
banana 20 15
soap 3 1
tshirt 3
# includes non-matching lines from both the files
$ join -a1 -a2 shopping_jan.txt shopping_feb.txt
apple 10
banana 20 15
fig 100
pen 2
soap 3 1
tshirt 3
</code></pre><p>If you use <code>-v</code> instead of <code>-a</code>, the output will have only the non-matching lines.<pre><code class=language-bash>$ join -v2 shopping_jan.txt shopping_feb.txt
fig 100
pen 2
$ join -v1 -v2 shopping_jan.txt shopping_feb.txt
apple 10
fig 100
pen 2
tshirt 3
</code></pre><h2 id=change-field-separator><a class=header href=#change-field-separator>Change field separator</a></h2><p>You can use the <code>-t</code> option to specify a single byte character as the field separator. The output field separator will be same as the value used for the <code>-t</code> option. Use <code>\0</code> to specify NUL as the separator. Empty string will cause entire input line content to be considered as keys. Depending on your shell you can use <a href=https://www.gnu.org/software/bash/manual/html_node/ANSI_002dC-Quoting.html>ANSI-C quoting</a> to use escapes like <code>\t</code> instead of a literal tab character.<pre><code class=language-bash>$ cat marks.csv
ECE,Raj,53
ECE,Joel,72
EEE,Moi,68
CSE,Surya,81
EEE,Raj,88
CSE,Moi,62
EEE,Tia,72
ECE,Om,92
CSE,Amy,67
$ cat dept.txt
CSE
ECE
# get all lines from marks.csv based on the first field keys in dept.txt
$ join -t, <(sort marks.csv) dept.txt
CSE,Amy,67
CSE,Moi,62
CSE,Surya,81
ECE,Joel,72
ECE,Om,92
ECE,Raj,53
</code></pre><h2 id=files-with-headers><a class=header href=#files-with-headers>Files with headers</a></h2><p>Use the <code>--header</code> option to ignore first lines of both the input files from sorting consideration. Without this option, the <code>join</code> command might still work correctly if unpairable lines aren't found, but it is preferable to use <code>--header</code> when applicable. This option will also help when <code>--check-order</code> option is active.<pre><code class=language-bash>$ cat report_1.csv
Name,Maths,Physics
Amy,78,95
Moi,88,75
Raj,67,76
$ cat report_2.csv
Name,Chemistry
Amy,85
Joel,78
Raj,72
$ join --check-order -t, report_1.csv report_2.csv
join: report_1.csv:2: is not sorted: Amy,78,95
$ join --check-order --header -t, report_1.csv report_2.csv
Name,Maths,Physics,Chemistry
Amy,78,95,85
Raj,67,76,72
</code></pre><h2 id=change-key-field><a class=header href=#change-key-field>Change key field</a></h2><p>By default, the first field of both the input files are used to combine the lines. You can use <code>-1</code> and <code>-2</code> options followed by a field number to specify a different field number. You can use the <code>-j</code> option if the field number is the same for both the files.<p>Recall that the key field is the first field in the output. You'll later see how to customize the output field order.<pre><code class=language-bash>$ cat names.txt
Amy
Raj
Tia
# combine based on the second field of the first file
# and the first field of the second file (default)
$ join -t, -1 2 <(sort -t, -k2,2 marks.csv) names.txt
Amy,CSE,67
Raj,ECE,53
Raj,EEE,88
Tia,EEE,72
</code></pre><h2 id=customize-output-field-list><a class=header href=#customize-output-field-list>Customize output field list</a></h2><p>Use the <code>-o</code> option to customize the fields required in the output and their order. Especially useful when the first field isn't the key. Each output field is specified as file number followed by a <code>.</code> character and then the field number. You can specify multiple fields separated by a <code>,</code> character. As a special case, you can use <code>0</code> to indicate the key field.<pre><code class=language-bash># output field order is 1st, 2nd and 3rd fields from the first file
$ join -t, -1 2 -o 1.1,1.2,1.3 <(sort -t, -k2,2 marks.csv) names.txt
CSE,Amy,67
ECE,Raj,53
EEE,Raj,88
EEE,Tia,72
# 1st field from the first file, 2nd field from the second file
# and then 2nd and 3rd fields from the first file
$ join --header -t, -o 1.1,2.2,1.2,1.3 report_1.csv report_2.csv
Name,Chemistry,Maths,Physics
Amy,85,78,95
Raj,72,67,76
</code></pre><h2 id=same-number-of-output-fields><a class=header href=#same-number-of-output-fields>Same number of output fields</a></h2><p>If you use <code>auto</code> as the argument for the <code>-o</code> option, first line of both the input files will be used to determine the number of output fields. If the other lines have extra fields, they will be discarded.<pre><code class=language-bash>$ join <(printf 'a 1 2\nb p q r') <(printf 'a 3 4\nb x y z')
a 1 2 3 4
b p q r x y z
$ join -o auto <(printf 'a 1 2\nb p q r') <(printf 'a 3 4\nb x y z')
a 1 2 3 4
b p q x y
</code></pre><p>If the other lines have lesser number of fields, the <code>-e</code> option will determine the string to be used as a filler (empty string is the default).<pre><code class=language-bash># the second line has two empty fields
$ join -o auto <(printf 'a 1 2\nb p') <(printf 'a 3 4\nb x')
a 1 2 3 4
b p x
$ join -o auto -e '-' <(printf 'a 1 2\nb p') <(printf 'a 3 4\nb x')
a 1 2 3 4
b p - x -
</code></pre><p>As promised earlier, here are some examples of filling fields for non-matching lines:<pre><code class=language-bash>$ join -o auto -a1 -e 'NA' shopping_jan.txt shopping_feb.txt
apple 10 NA
banana 20 15
soap 3 1
tshirt 3 NA
$ join -o auto -a1 -a2 -e 'NA' shopping_jan.txt shopping_feb.txt
apple 10 NA
banana 20 15
fig NA 100
pen NA 2
soap 3 1
tshirt 3 NA
</code></pre><h2 id=set-operations><a class=header href=#set-operations>Set operations</a></h2><p>This section covers whole line set operations you can perform on already sorted input files. Equivalent <code>sort</code> and <code>uniq</code> solutions will also be mentioned as comments (useful for unsorted inputs). Assume that there are no duplicate lines within an input file.<p>These two sorted input files will be used for the examples to follow:<pre><code class=language-bash>$ paste colors_1.txt colors_2.txt
Blue Black
Brown Blue
Orange Green
Purple Orange
Red Pink
Teal Red
White White
</code></pre><p>Here's how you can get <em>union</em> and <em>symmetric difference</em> results. Recall that <code>-t ''</code> will cause the entire input line content to be considered as keys.<pre><code class=language-bash># union
# unsorted input: sort -u colors_1.txt colors_2.txt
$ join -t '' -a1 -a2 colors_1.txt colors_2.txt
Black
Blue
Brown
Green
Orange
Pink
Purple
Red
Teal
White
# symmetric difference
# unsorted input: sort colors_1.txt colors_2.txt | uniq -u
$ join -t '' -v1 -v2 colors_1.txt colors_2.txt
Black
Brown
Green
Pink
Purple
Teal
</code></pre><p>Here's how you can get <em>intersection</em> and <em>difference</em> results. The equivalent <code>comm</code> solutions for sorted input is also mentioned in the comments.<pre><code class=language-bash># intersection, same as: comm -12 colors_1.txt colors_2.txt
# unsorted input: sort colors_1.txt colors_2.txt | uniq -d
$ join -t '' colors_1.txt colors_2.txt
Blue
Orange
Red
White
# difference, same as: comm -13 colors_1.txt colors_2.txt
# unsorted input: sort colors_1.txt colors_1.txt colors_2.txt | uniq -u
$ join -t '' -v2 colors_1.txt colors_2.txt
Black
Green
Pink
# difference, same as: comm -23 colors_1.txt colors_2.txt
# unsorted input: sort colors_1.txt colors_2.txt colors_2.txt | uniq -u
$ join -t '' -v1 colors_1.txt colors_2.txt
Brown
Purple
Teal
</code></pre><p>As mentioned before, <code>join</code> will display all the combinations if there are duplicate entries. Here's an example to show the differences between <code>sort</code>, <code>comm</code> and <code>join</code> solutions for displaying common lines:<pre><code class=language-bash>$ paste list_1.txt list_2.txt
apple cherry
banana cherry
cherry mango
cherry papaya
cherry
cherry
# only one entry per common line
$ sort list_1.txt list_2.txt | uniq -d
cherry
# minimum of 'no. of entries in file1' and 'no. of entries in file2'
$ comm -12 list_1.txt list_2.txt
cherry
cherry
# 'no. of entries in file1' multiplied by 'no. of entries in file2'
$ join -t '' list_1.txt list_2.txt
cherry
cherry
cherry
cherry
cherry
cherry
cherry
cherry
</code></pre><h2 id=nul-separator><a class=header href=#nul-separator>NUL separator</a></h2><p>Use the <code>-z</code> option if you want to use NUL character as the line separator. In this scenario, <code>join</code> will ensure to add a final NUL character even if not present in the input.<pre><code class=language-bash>$ join -z <(printf 'a 1\0b x') <(printf 'a 2\0b y') | cat -v
a 1 2^@b x y^@
</code></pre><h2 id=alternatives><a class=header href=#alternatives>Alternatives</a></h2><p>Here are some alternate commands you can explore if <code>join</code> isn't enough to solve your task. These alternatives do not require input to be sorted.<ul><li><a href=https://github.com/yarrow/zet>zet</a> — set operations on one or more input files<li><a href=https://learnbyexample.github.io/learn_gnugrep_ripgrep/frequently-used-options.html#comparing-lines-between-files>Comparing lines between files</a> section from my <strong>GNU grep</strong> ebook<li><a href=https://learnbyexample.github.io/learn_gnuawk/two-file-processing.html>Two file processing</a> chapter from my <strong>GNU awk</strong> ebook, has examples for both line and field based comparisons<li><a href=https://learnbyexample.github.io/learn_perl_oneliners/two-file-processing.html>Two file processing</a> chapter from my <strong>Perl one-liners</strong> ebook, has examples for both line and field based comparisons</ul><h2 id=exercises><a class=header href=#exercises>Exercises</a></h2><blockquote><p><img alt=info src=images/info.svg> The <a href=https://github.com/learnbyexample/cli_text_processing_coreutils/tree/main/exercises>exercises</a> directory has all the files used in this section.</blockquote><blockquote><p><img alt=info src=./images/info.svg> Assume that the input files are already sorted for these exercises.</blockquote><p><strong>1)</strong> Use appropriate options to get the expected outputs shown below.<pre><code class=language-bash># no output
$ join <(printf 'apple 2\nfig 5') <(printf 'Fig 10\nmango 4')
# expected output 1
##### add your solution here
fig 5 10
# expected output 2
##### add your solution here
apple 2
fig 5 10
mango 4
</code></pre><p><strong>2)</strong> Use the <code>join</code> command to display only the non-matching lines based on the first field.<pre><code class=language-bash>$ cat j1.txt
apple 2
fig 5
lemon 10
tomato 22
$ cat j2.txt
almond 33
fig 115
mango 20
pista 42
# first field items present in j1.txt but not j2.txt
##### add your solution here
apple 2
lemon 10
tomato 22
# first field items present in j2.txt but not j1.txt
##### add your solution here
almond 33
mango 20
pista 42
</code></pre><p><strong>3)</strong> Filter lines from <code>j1.txt</code> and <code>j2.txt</code> that match the items from <code>s1.txt</code>.<pre><code class=language-bash>$ cat s1.txt
apple
coffee
fig
honey
mango
pasta
sugar
tea
##### add your solution here
apple 2
fig 115
fig 5
mango 20
</code></pre><p><strong>4)</strong> Join the <code>marks_1.csv</code> and <code>marks_2.csv</code> files to get the expected output shown below.<pre><code class=language-bash>$ cat marks_1.csv
Name,Biology,Programming
Er,92,77
Ith,100,100
Lin,92,100
Sil,86,98
$ cat marks_2.csv
Name,Maths,Physics,Chemistry
Cy,97,98,95
Ith,100,100,100
Lin,78,83,80
##### add your solution here
Name,Biology,Programming,Maths,Physics,Chemistry
Ith,100,100,100,100,100
Lin,92,100,78,83,80
</code></pre><p><strong>5)</strong> By default, the first field is used to combine the lines. Which options are helpful if you want to change the key field to be used for joining?<p><strong>6)</strong> Join the <code>marks_1.csv</code> and <code>marks_2.csv</code> files to get the expected output with specific fields as shown below.<pre><code class=language-bash>##### add your solution here
Name,Programming,Maths,Biology
Ith,100,100,100
Lin,100,78,92
</code></pre><p><strong>7)</strong> Join the <code>marks_1.csv</code> and <code>marks_2.csv</code> files to get the expected output shown below. Use <code>50</code> as the filler data.<pre><code class=language-bash>##### add your solution here
Name,Biology,Programming,Maths,Physics,Chemistry
Cy,50,50,97,98,95
Er,92,77,50,50,50
Ith,100,100,100,100,100
Lin,92,100,78,83,80
Sil,86,98,50,50,50
</code></pre><p><strong>8)</strong> When you use the <code>-o auto</code> option, what'd happen to the extra fields compared to those in the first lines of the input data?<p><strong>9)</strong> From the input files <code>j3.txt</code> and <code>j4.txt</code>, filter only the lines are unique — i.e. lines that are not common to these files. Assume that the input files do not have duplicate entries.<pre><code class=language-bash>$ cat j3.txt
almond
apple pie
cold coffee
honey
mango shake
pasta
sugar
tea
$ cat j4.txt
apple
banana shake
coffee
fig
honey
mango shake
milk
tea
yeast
##### add your solution here
almond
apple
apple pie
banana shake
coffee
cold coffee
fig
milk
pasta
sugar
yeast
</code></pre><p><strong>10)</strong> From the input files <code>j3.txt</code> and <code>j4.txt</code>, filter only the lines are common to these files.<pre><code class=language-bash>##### add your solution here
honey
mango shake
tea
</code></pre></main><nav aria-label="Page navigation"class=nav-wrapper><a aria-label="Previous chapter"class="mobile-nav-chapters previous"title="Previous chapter"aria-keyshortcuts=Left href=comm.html rel=prev> <i class="fa fa-angle-left"></i> </a><a aria-label="Next chapter"class="mobile-nav-chapters next"title="Next chapter"aria-keyshortcuts=Right href=nl.html rel=next> <i class="fa fa-angle-right"></i> </a><div style="clear: both"></div></nav></div></div><nav aria-label="Page navigation"class=nav-wide-wrapper><a aria-label="Previous chapter"class="nav-chapters previous"title="Previous chapter"aria-keyshortcuts=Left href=comm.html rel=prev> <i class="fa fa-angle-left"></i> </a><a aria-label="Next chapter"class="nav-chapters next"title="Next chapter"aria-keyshortcuts=Right href=nl.html rel=next> <i class="fa fa-angle-right"></i> </a></nav></div><script>window.playground_copyable = true;</script><script charset=utf-8 src=elasticlunr.min.js></script><script charset=utf-8 src=mark.min.js></script><script charset=utf-8 src=searcher.js></script><script charset=utf-8 src=clipboard.min.js></script><script charset=utf-8 src=highlight.js></script><script charset=utf-8 src=book.js></script><script src=sidebar.js></script>