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diff --git a/shell-workshop/session.html b/shell-workshop/session.html new file mode 100644 index 0000000..1a5da6e --- /dev/null +++ b/shell-workshop/session.html @@ -0,0 +1,381 @@ +<h2>Shell Input</h2> + +<pre><code>sh@sleipnir1:~$ vim hello.sh +sh@sleipnir1:~$ cat hello.sh +echo Hello world +sh@sleipnir1:~$ sh hello.sh +Hello world +sh@sleipnir1:~$ sh -c 'echo Hello world' +Hello world +sh@sleipnir1:~$ echo Hello world +Hello world +</code></pre> + +<h2>Comments, Magic Number Behavior, and File Modes</h2> + +<pre><code>sh@sleipnir1:~$ vim hello.sh +sh@sleipnir1:~$ cat hello.sh +#! /bin/sh +# This is a comment +echo Hello world +sh@sleipnir1:~$ ./hello.sh +-su: ./hello.sh: Permission denied +sh@sleipnir1:~$ ls -l hello.sh +-rw-r--r-- 1 sh sh 48 Mar 30 13:26 hello.sh +sh@sleipnir1:~$ chmod a+x hello.sh +sh@sleipnir1:~$ ls -l hello.sh +-rwxr-xr-x 1 sh sh 48 Mar 30 13:26 hello.sh +sh@sleipnir1:~$ ./hello.sh +Hello world +</code></pre> + +<h2>Field Splitting and Quoting</h2> + +<pre><code>sh@sleipnir1:~$ mkdir foo bar +sh@sleipnir1:~$ ls +bar foo hello.sh +sh@sleipnir1:~$ rmdir foo bar +sh@sleipnir1:~$ mkdir foo\ bar +sh@sleipnir1:~$ ls +foo bar hello.sh +sh@sleipnir1:~$ rmdir foo\ bar +sh@sleipnir1:~$ ls +hello.sh +sh@sleipnir1:~$ mkdir 'foo bar +> baz' +sh@sleipnir1:~$ ls +foo bar?baz hello.sh +sh@sleipnir1:~$ rmdir 'foo bar +> baz' +sh@sleipnir1:~$ ls +hello.sh +sh@sleipnir1:~$ mkdir "foo bar baz" +sh@sleipnir1:~$ ls +foo bar baz hello.sh +</code></pre> + +<h2>Tilde Expansion</h2> + +<pre><code>sh@sleipnir1:~$ echo ~ +/home/sh +sh@sleipnir1:~$ ls ~sh-foo +another-directory another-file bar baz foo some-directory some-file +sh@sleipnir1:~$ ls ~sh-foo/some-directory +Hey, this is a cool file! +</code></pre> + +<h2>Pathname Expansion</h2> + +<pre><code>sh@sleipnir1:~$ echo ~sh-foo/*-file +/home/sh-foo/another-file /home/sh-foo/some-file +sh@sleipnir1:~$ echo ~sh-foo/ba*/file +/home/sh-foo/bar/file /home/sh-foo/baz/file +sh@sleipnir1:~$ echo ~sh-foo/ba[a-r]/file +/home/sh-foo/bar/file +sh@sleipnir1:~$ echo ~sh-foo/ba[p-z]/file +/home/sh-foo/bar/file /home/sh-foo/baz/file +</code></pre> + +<h2>Parameter Assignment</h2> + +<pre><code>sh@sleipnir1:~$ myparam=foo +sh@sleipnir1:~$ mynum=1 +</code></pre> + +<h2>Parameter Expansion</h2> + +<pre><code>sh@sleipnir1:~$ echo ${myparam} +foo +sh@sleipnir1:~$ echo ${nullparam:-default} +default +sh@sleipnir1:~$ echo ${#myparam} +3 +sh@sleipnir1:~$ file=main.c +sh@sleipnir1:~$ echo ${file%.c}.o +main.o +sh@sleipnir1:~$ dir=foo/bar/baz +sh@sleipnir1:~$ echo ${dir##*/} +baz +</code></pre> + +<h2>Positional Parameters</h2> + +<pre><code>sh@sleipnir1:~$ vim pos-params.sh +sh@sleipnir1:~$ cat pos-params.sh +#! /bin/sh +echo ${1} +echo ${2} +sh@sleipnir1:~$ chmod a+x pos-params.sh +sh@sleipnir1:~$ ./pos-params.sh foo +foo + +sh@sleipnir1:~$ sh pos-params.sh foo bar baz +foo +bar +</code></pre> + +<h2>Special Parameters</h2> + +<pre><code>sh@sleipnir1:~$ vim spec-params.sh +sh@sleipnir1:~$ cat spec-params.sh +#! /bin/sh + +echo Number of positional parameters: ${#} +echo Positional parameters: ${@} +echo Script name: ${0} +sh@sleipnir1:~$ sh spec-params.sh foo bar baz +Number of positional parameters: 3 +Positional parameters: foo bar baz +Script name: spec-params.sh +</code></pre> + +<h2>Exit Statuses</h2> + +<pre><code>sh@sleipnir1:~$ vim spec-params.sh +sh@sleipnir1:~$ cat spec-params.sh +#! /bin/sh + +echo Number of positional parameters: ${#} +echo Positional parameters: ${@} +echo Script name: ${0} +true +echo ${?} +false +echo ${?} +sh@sleipnir1:~$ sh spec-params.sh foo bar baz +Number of positional parameters: 3 +Positional parameters: foo bar baz +Script name: spec-params.sh +0 +1 +</code></pre> + +<h2>Shell Variables and Links <code>.</code> and <code>..</code></h2> + +<pre><code>sh@sleipnir1:~$ echo ${HOME} +/home/sh +sh@sleipnir1:~$ echo ${PWD} +/home/sh +sh@sleipnir1:~$ ls +foo bar baz hello.sh pos-params.sh spec-params.sh +sh@sleipnir1:~$ cd foo\ bar\ baz/ +sh@sleipnir1:~/foo bar baz$ echo ${PWD} +/home/sh/foo bar baz +sh@sleipnir1:~/foo bar baz$ ls . +sh@sleipnir1:~/foo bar baz$ mkdir file1 file2 +sh@sleipnir1:~/foo bar baz$ ls . +file1 file2 +sh@sleipnir1:~/foo bar baz$ ls .. +foo bar baz hello.sh pos-params.sh spec-params.sh +sh@sleipnir1:~/foo bar baz$ cd .. +sh@sleipnir1:~$ echo ${PWD} +/home/sh +sh@sleipnir1:~$ PS1='$ ' +$ PS1='PROMPT> ' +PROMPT> echo Hello +Hello +PROMPT> PS1='$ ' +$ echo Hello \ +> World +Hello World +</code></pre> + +<h2>Command Substitution</h2> + +<pre><code>$ filepath=$(basename ~sh-foo/bar/file) +$ echo ${filepath} +file +</code></pre> + +<h2>Arithmetic Expansion</h2> + +<pre><code>$ echo $((2+3)) +5 +$ echo $((0x10 + 4)) +20 +$ i=0 +$ i=$(($i + 1)) +$ echo ${i} +1 +$ i=$(($i + 1)) +$ echo ${i} +2 +$ i=$(($i + 1)) +$ echo ${i} +3 +</code></pre> + +<h2>Simple Commands</h2> + +<pre><code>$ i=0 echo Hello +Hello +</code></pre> + +<h2>Command Search and Execution</h2> + +<pre><code>$ echo ${PATH} +/usr/local/bin:/usr/bin:/bin:/usr/local/games:/usr/games +$ ./hello.sh +Hello world +$ hello.sh +-su: hello.sh: command not found +$ ls +foo bar baz hello.sh pos-params.sh spec-params.sh +$ PATH=${PATH}:${HOME} +$ echo ${PATH} +/usr/local/bin:/usr/bin:/bin:/usr/local/games:/usr/games:/home/sh +$ hello.sh +Hello world +</code></pre> + +<h2>Pipelines</h2> + +<pre><code>$ ! true +$ echo ${?} +1 +$ ! false +$ echo ${?} +0 +$ true +$ echo ${?} +0 +$ false +$ echo ${?} +1 +</code></pre> + +<h2>Lists</h2> + +<pre><code>$ false && echo foo || echo bar +bar +$ true || echo foo && echo bar +bar +</code></pre> + +<h2><code>test</code> Command and <code>if</code> Construct</h2> + +<pre><code>$ [ foo = foo ] && echo equal || echo not equal +equal +$ if [ foo = foo ]; then echo equal else echo not equal; fi +equal else echo not equal +$ if [ foo = foo ]; then echo equal; else echo not equal; fi +equal +$ if [ foo = foo ]; then +> echo equal +> else +> echo not equal +> fi +equal +</code></pre> + +<h2><code>while</code> Loop</h2> + +<pre><code>$ i=0 +$ while [ ${i} -lt 5 ]; do +> echo ${i} +> i=$(($i + 1)) +> done +0 +1 +2 +3 +4 +$ vim param-loop.sh +$ cat param-loop.sh +while [ ${#} -gt 0 ]; do + echo Parameter: ${1} + shift +done +$ sh param-loop.sh foo bar baz +Parameter: foo +Parameter: bar +Parameter: baz +</code></pre> + +<h2><code>for</code> Loop</h2> + +<pre><code>$ for param in foo bar baz; do +> echo ${param} +> done +foo +bar +baz +</code></pre> + +<h2><code>case</code> Construct</h2> + +<pre><code>$ param=foo +$ case ${param} in +> f*) +> echo starts with f +> ;; +> b*) +> echo starts with b +> ;; +> esac +starts with f +</code></pre> + +<h2>Functions</h2> + +<pre><code>$ print_hello() +> { +> echo Hello world +> } +$ print_hello +Hello world +$ print_params() +> { +> echo ${@} +> } +$ print_params 1 2 3 +1 2 3 +</code></pre> + +<h2>Input/Output Redirection</h2> + +<pre><code>$ echo Hello world > hello-file +$ cat hello-file +Hello world +$ echo Hello world > hello-file +$ echo Hello world > hello-file +$ echo Hello world > hello-file +$ cat hello-file +Hello world +$ echo Hello world >> hello-file +$ echo Hello world >> hello-file +$ cat hello-file +Hello world +Hello world +Hello world +$ vim read-file.sh +$ cat read-file.sh +while read line; do + echo Line: ${line} +done < myfile.txt +$ sh read-file.sh +Line: line one +Line: line two +Line: some other line +$ vim read-file.sh +$ cat read-file.sh +while read field1 field2; do + echo Line: ${field1}, ${field2} +done < myfile.txt +$ sh read-file.sh +Line: line, one +Line: line, two +Line: some, other line +$ echo Hello world > /dev/null +$ sh -c not-a-command +sh: 1: not-a-command: not found +$ sh -c not-a-command 2> /dev/null +$ while read line; do +> echo Line: ${line} +> done <<EOF +> this is input +> some more input +> EOF +Line: this is input +Line: some more input +</code></pre> |