One-Day Study Shell: Part 3 Shell test command

谁借莪１个温暖的怀抱￠ 2022-10-09 12:22 23阅读 0赞

### One-Day Study Shell: Part 3 Shell test command ###

*   *  Value Test
     *  String Test
     *  File Test

## Value Test ##

<table> 
 <thead> 
  <tr> 
   <th>parameter</th> 
   <th>description</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td><code>-eq</code></td> 
   <td><code>if "=" ; true</code></td> 
  </tr> 
  <tr> 
   <td><code>-ne</code></td> 
   <td><code>if "!=" ;true</code></td> 
  </tr> 
  <tr> 
   <td><code>-gt</code></td> 
   <td><code>if "&gt;" ; true</code></td> 
  </tr> 
  <tr> 
   <td><code>-ge</code></td> 
   <td><code>if "&gt;=" ; true</code></td> 
  </tr> 
  <tr> 
   <td><code>-lt</code></td> 
   <td><code>if "&lt;" ; true</code></td> 
  </tr> 
  <tr> 
   <td><code>-le</code></td> 
   <td><code>"if "&lt;=" ; true</code></td> 
  </tr> 
 </tbody> 
</table>

#!/bin/bash
    # author:keke
    
    value1=10
    value2=20
    
    if test $[value1] -eq $[value2]
    then
        echo "value1 = value2"
    elif test $[value1] -gt $[value2]
    then
        echo "value1 < value2"
    else
        echo "value1 < value2"
    fi

#Output
    value1 < value2

## String Test ##

<table> 
 <thead> 
  <tr> 
   <th>parameter</th> 
   <th>description</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td><code>=</code></td> 
   <td><code>if "=" ; true</code></td> 
  </tr> 
  <tr> 
   <td><code>!=</code></td> 
   <td><code>if "!=" ;true</code></td> 
  </tr> 
  <tr> 
   <td><code>-z</code></td> 
   <td><code>if string length is zero ; true</code></td> 
  </tr> 
  <tr> 
   <td><code>-n</code></td> 
   <td><code>if string length is not zero ; true</code></td> 
  </tr> 
 </tbody> 
</table>

#!/bin/bash
    # author:keke
    
    string1="kekememory"
    string2="kekememor"
    
    if test $string1 = $string2
    then
        echo "string1 = string2"
    else
        echo "string1 != string2"
    fi

#Output
    string1 != string2

## File Test ##

<table> 
 <thead> 
  <tr> 
   <th>parameter</th> 
   <th>description</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td><code>-e</code></td> 
   <td><code>if file exits ; true</code></td> 
  </tr> 
  <tr> 
   <td><code>-r</code></td> 
   <td><code>if file exists &amp;&amp; only-read ;true</code></td> 
  </tr> 
  <tr> 
   <td><code>-w</code></td> 
   <td><code>if file exists &amp;&amp; write-available ; true</code></td> 
  </tr> 
  <tr> 
   <td><code>-x</code></td> 
   <td><code>if file exists &amp;&amp; excuate-available ; true</code></td> 
  </tr> 
  <tr> 
   <td><code>-s</code></td> 
   <td><code>if file exists &amp;&amp; more than a string ; true</code></td> 
  </tr> 
  <tr> 
   <td><code>-d</code></td> 
   <td><code>if file exists &amp;&amp; is directory ; true</code></td> 
  </tr> 
  <tr> 
   <td><code>-f</code></td> 
   <td><code>if file exists &amp;&amp; normal file ; true</code></td> 
  </tr> 
  <tr> 
   <td><code>-c</code></td> 
   <td><code>if file exists &amp;&amp; char-type file ; true</code></td> 
  </tr> 
  <tr> 
   <td><code>-b</code></td> 
   <td><code>if file exists &amp;&amp; block-type file ; true</code></td> 
  </tr> 
 </tbody> 
</table>

#!/bin/bash
    # author:keke
    cd /bin
    
    if test -e ./bash
    then
        echo "File exists!"
    else
        echo "No existied file~"
    fi

#!/bin/bash
    # author:keke
    cd /bin
    
    if test -e ./sys
    then
        echo "File exists!"
    else
        echo "No existied file~"
    fi

#Output1:
    File exists!
    #Output2:
    No existied file~