entityMap|blocks|key|57tr7|text|嗯，差不多吧：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|amsfh|{+#+your+'try'+block
++++executeCommandWhichCanFail+&&
++++mv+output
}+%7C%7C+{+#+your+'catch'+block
++++mv+log
}

+rm+tmp+#+finally:+this+will+always+happen|code-block|syntax|javascript^0|0^^$0|$]|1|@$2|3|4|5|6|7|8|H|9|@]|A|@]|B|$]]|$2|C|4|D|6|E|8|I|9|@]|A|@]|B|$F|G]]]]

Well, sort of:

<pre class="lang-bsh prettyprint-override"><code>{ # your 'try' block
 executeCommandWhichCanFail &amp;&amp;
 mv output
} || { # your 'catch' block
 mv log
}

 rm tmp # finally: this will always happen
</code></pre>

entityMap|blocks|key|6n3j1|text|mv使用两个参数，因此您可能真的希望cat输出文件的内容：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|fkbd1|echo+`{+execCommand+&&+cat+output+;+}+%7C%7C+cat+log`
rm+-f+tmp|code-block|syntax|javascript^0|0|2|0^^$0|$]|1|@$2|3|4|5|6|7|8|L|9|@$A|M|B|N|C|D]]|E|@]|F|$]]|$2|G|4|H|6|I|8|O|9|@]|E|@]|F|$J|K]]]]

<code>mv</code> takes two parameters, so may be you really wanted to cat the output file's contents:

<pre><code>echo `{ execCommand &amp;&amp; cat output ; } || cat log`
rm -f tmp
</code></pre>

entityMap|blocks|key|7blvb|text|根据您的示例，无论脚本如何退出，您似乎都在尝试执行类似于始终删除临时文件的操作。要在Bash中执行此操作，请尝试trap内置命令来捕获EXIT信号。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|a6a0u|#!/bin/bash

trap+'rm+tmp'+EXIT

if+executeCommandWhichCanFail;+then
++++mv+output
else
++++mv+log
++++exit+1+#Exit+with+failure
fi

exit+0+#Exit+with+success|code-block|syntax|javascript|e4878|rm+tmp语句中的trap始终在脚本退出时执行，因此将始终尝试删除文件"tmp“。|6fkhk|还可以重置已安装的陷阱；调用仅带信号名称的陷阱将重置信号处理程序。|97lrn|trap+EXIT|js|31h8f|有关更多详细信息，请参阅bash手册页面：man+bash^0|1K|4|1V|4|0|0|0|6|A|4|0|0|0|L|8^^$0|$]|1|@$2|3|4|5|6|7|8|U|9|@$A|V|B|W|C|D]|$A|X|B|Y|C|D]]|E|@]|F|$]]|$2|G|4|H|6|I|8|Z|9|@]|E|@]|F|$J|K]]|$2|L|4|M|6|7|8|10|9|@$A|11|B|12|C|D]|$A|13|B|14|C|D]]|E|@]|F|$]]|$2|N|4|O|6|7|8|15|9|@]|E|@]|F|$]]|$2|P|4|Q|6|I|8|16|9|@]|E|@]|F|$J|R]]|$2|S|4|T|6|7|8|17|9|@$A|18|B|19|C|D]]|E|@]|F|$]]]]

Based on your example, it looks like you are trying to do something akin to always deleting a temporary file, regardless of how a script exits. In Bash to do this try the <code>trap</code> builtin command to trap the <code>EXIT</code> signal.

<pre><code>#!/bin/bash

trap 'rm tmp' EXIT

if executeCommandWhichCanFail; then
 mv output
else
 mv log
 exit 1 #Exit with failure
fi

exit 0 #Exit with success
</code></pre>

The <code>rm tmp</code> statement in the <code>trap</code> is always executed when the script exits, so the file "tmp" will always tried to be deleted.

Installed traps can also be reset; a call to trap with only a signal name will reset the signal handler.

<pre><code>trap EXIT
</code></pre>

For more details, see the bash manual page: <code>man bash</code>

entityMap|blocks|key|3mepc|text|另一种方法是：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|2qdu|set+-e;++#+stop+on+errors

mkdir+-p+"$HOME/tmp/whatevs"

exit_code=0

(
++set+%2Be;
++(
++++set+-e;
++++echo+'foo'
++++echo+'bar'
++++echo+'biz'
++)
++exit_code="$?"
)

rm+-rf+"$HOME/tmp/whatevs"

if+[[+"exit_code"+!=+'0'+]];+then
+++echo+'failed';
fi|code-block|syntax|javascript|2rssn|尽管上面并没有提供任何好处：|qm47|set+-e;++#+stop+on+errors

mkdir+-p+"$HOME/tmp/whatevs"

exit_code=0

(
++++set+-e;
++++echo+'foo'
++++echo+'bar'
++++echo+'biz'
++++exit+44;
++++exit+43;

)+%7C%7C+{
+++exit_code="$?"++#+exit+code+of+last+command+which+is+44
}

rm+-rf+"$HOME/tmp/whatevs"

if+[[+"exit_code"+!=+'0'+]];+then
+++echo+'failed';
fi^0|0|0|0^^$0|$]|1|@$2|3|4|5|6|7|8|L|9|@]|A|@]|B|$]]|$2|C|4|D|6|E|8|M|9|@]|A|@]|B|$F|G]]|$2|H|4|I|6|7|8|N|9|@]|A|@]|B|$]]|$2|J|4|K|6|E|8|O|9|@]|A|@]|B|$F|G]]]]

Another way to do it would be:

<pre><code>set -e; # stop on errors

mkdir -p "$HOME/tmp/whatevs"

exit_code=0

(
 set +e;
 (
 set -e;
 echo 'foo'
 echo 'bar'
 echo 'biz'
 )
 exit_code="$?"
)

rm -rf "$HOME/tmp/whatevs"

if [[ "exit_code" != '0' ]]; then
 echo 'failed';
fi 
</code></pre>

although the above doesn't really offer any benefit over:

<pre><code>set -e; # stop on errors

mkdir -p "$HOME/tmp/whatevs"

exit_code=0

(
 set -e;
 echo 'foo'
 echo 'bar'
 echo 'biz'
 exit 44;
 exit 43;

) || {
 exit_code="$?" # exit code of last command which is 44
}

rm -rf "$HOME/tmp/whatevs"

if [[ "exit_code" != '0' ]]; then
 echo 'failed';
fi 
</code></pre>

entityMap|0|type|LINK|mutability|MUTABLE|data|url|https://stackoverflow.com/a/58689419/2075630|blocks|key|6079f|text|警告:退出陷阱不是始终被执行了。自从写了这个答案以来，我遇到了一些情况，我的退出陷阱不会被执行，导致文件丢失，原因我还没有找到。|unstyled|depth|inlineStyleRanges|entityRanges|ac6bo|当我使用以下命令停止python脚本时，出现了该问题Ctrl%2BC，它使用退出陷阱执行了bash脚本--这实际上应该导致执行退出陷阱，因为退出陷阱是在SIGINT在狂欢中。|offset|length|style|CODE|8khs|所以，虽然trap+..+exit对于清理工作很有用，但仍有一些场景不会执行，最明显的情况是断电和接收SIGKILL。|9gm6g|当我添加额外的选项或以其他方式更改它们时，我经常会得到非常大的bash脚本。当bash脚本包含很多函数时，使用“陷阱退出”可能会变得非常重要。|6dfc7|例如，考虑如下所调用的脚本|4triu|dotask+TASK+[ARG+...]|code-block|syntax|js|2bk5s|其中每个TASK可能由多个子步骤组成，需要在其间执行清理。|8vbs1|在这种情况下，使用子外壳来产生范围内的退出陷阱是有帮助的，例如|2apcu|function+subTask+(
++++local+tempFile=$(mktemp)
++++trap+"rm+'${tempFile}'"+exit
++++...
)|javascript|7nkdh|但是，使用子shell可能很棘手，因为它们不能设置父shell的全局变量。|d1dc6|此外，编写单个出口陷阱通常是不方便的。例如，清理步骤可能取决于函数在遇到错误之前走了多远。如果能够进行RAII样式清理声明，那将是一件很好的事情：|9jnkh|function+subTask+(
++++...
++++onExit+'rm+tmp.1'
++++...
++++onExit+'rm+tmp.2'
++++...
)|bm2b3|看起来很明显要使用像这样的东西|cdni7|handlers=""
function+onExit+{+handlers%2B="$1;";+trap+"$handlers"+exit;+}|f70pl|更新陷阱。但是对于嵌套子shell，这将失败，因为它将导致提前执行父shell的处理程序。客户端代码必须显式地重置handlers变量。|3llo9|中讨论的解决方案[同一个signal]的多个bash陷阱，它通过使用以下输出修补陷阱trap+-p+EXIT同样也会失败:即使subshell没有继承EXIT陷阱，trap+-p+exit将显示父shell的处理程序，因此再次需要手动重置。^0|0|Q|6|22|6|0|5|C|1F|7|0|0|0|0|4|4|0|0|0|0|0|0|0|0|1L|8|0|16|C|23|4|2A|C|8|B|0^^$0|$1|$2|3|4|5|6|$7|8]]]|9|@$A|B|C|D|2|E|F|1K|G|@]|H|@]|6|$]]|$A|I|C|J|2|E|F|1L|G|@$K|1M|L|1N|M|N]|$K|1O|L|1P|M|N]]|H|@]|6|$]]|$A|O|C|P|2|E|F|1Q|G|@$K|1R|L|1S|M|N]|$K|1T|L|1U|M|N]]|H|@]|6|$]]|$A|Q|C|R|2|E|F|1V|G|@]|H|@]|6|$]]|$A|S|C|T|2|E|F|1W|G|@]|H|@]|6|$]]|$A|U|C|V|2|W|F|1X|G|@]|H|@]|6|$X|Y]]|$A|Z|C|10|2|E|F|1Y|G|@$K|1Z|L|20|M|N]]|H|@]|6|$]]|$A|11|C|12|2|E|F|21|G|@]|H|@]|6|$]]|$A|13|C|14|2|W|F|22|G|@]|H|@]|6|$X|15]]|$A|16|C|17|2|E|F|23|G|@]|H|@]|6|$]]|$A|18|C|19|2|E|F|24|G|@]|H|@]|6|$]]|$A|1A|C|1B|2|W|F|25|G|@]|H|@]|6|$X|15]]|$A|1C|C|1D|2|E|F|26|G|@]|H|@]|6|$]]|$A|1E|C|1F|2|W|F|27|G|@]|H|@]|6|$X|15]]|$A|1G|C|1H|2|E|F|28|G|@$K|29|L|2A|M|N]]|H|@]|6|$]]|$A|1I|C|1J|2|E|F|2B|G|@$K|2C|L|2D|M|N]|$K|2E|L|2F|M|N]|$K|2G|L|2H|M|N]]|H|@$K|2I|L|2J|A|2K]]|6|$]]]]

Warning: exit traps are not always excuted. Since writing this answer I have run into situations, where my exit trap would not be executed, causing loss of files, the reason of which I haven't found yet.
The issue occurred when I stopped a python script with <code>Ctrl+C</code>, which in turn had executed a bash script using exit traps -- which actually should cause the exit traps to be executed, since exit traps are executed on <code>SIGINT</code> in bash.
So, while <code>trap .. exit</code> is useful for cleanup, there are stil scenarios where it won't be executed, the most obvious ones being power outages and receiving <code>SIGKILL</code>.
<hr />
I often end up with bash scripts becoming quite large, as I add additional options, or otherwise change them. When a bash-script contains a lot of functions, using 'trap EXIT' may become non-trivial.
For instance, consider a script invoked as
<pre><code>dotask TASK [ARG ...]
</code></pre>
where each <code>TASK</code> may consists of substeps, where it is desirable to perform cleanup in between.
In this case, it is helpful to work with subshells to produce scoped exit traps, e.g.
<pre><code>function subTask (
 local tempFile=$(mktemp)
 trap &quot;rm '${tempFile}'&quot; exit
 ...
)
</code></pre>
However, working with subshells can be tricky, as they can't set global variables of the parent shell.
Additionally, it is often inconvenient to write a single exit trap. For instance, the cleanup steps may depend on how far a function came before encountering an error. It would be nice to be able to make RAII style cleanup declarations:
<pre><code>function subTask (
 ...
 onExit 'rm tmp.1'
 ...
 onExit 'rm tmp.2'
 ...
)
</code></pre>
It would seem obvious to use something like
<pre><code>handlers=&quot;&quot;
function onExit { handlers+=&quot;$1;&quot;; trap &quot;$handlers&quot; exit; }
</code></pre>
to update the trap. But this fails for nested subshells, as it would cause premature execution of the parent shell's handlers. The client code would have to explicitly reset the <code>handlers</code> variable at the beginning of the subshell.
Solutions discussed in <a href="https://stackoverflow.com/a/58689419/2075630">[multiple bash traps for the same signal]</a>, which patch the trap by using the output from <code>trap -p EXIT</code> will equally fail: Even though subshells don't inherit the <code>EXIT</code> trap, <code>trap -p exit</code> will display the parent shell's handler so, again, manual resetting is needed.

entityMap|blocks|key|2u2mp|text|我在我的脚本中成功地使用了以下语法：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|59qd7|#+Try,+catch,+finally
(echo+"try+this")+&&+(echo+"and+this")+%7C%7C+echo+"this+is+the+catch+statement!"

#+this+is+the+'finally'+statement
echo+"finally+this"|code-block|syntax|javascript|apspb|如果其中一条try语句抛出错误或以exit+1，然后解释器转到catch语句，然后转到finally语句。|offset|length|style|CODE|5sh04|如果两个try语句都成功(和/或以exit)时，解释器将跳过catch语句，然后运行finally语句。|knlt|示例_1：|dfu9v|goodFunction1(){
++#+this+function+works+great
++echo+"success1"
}

goodFunction2(){
++#+this+function+works+great
++echo+"success2"
++exit
}

(goodFunction1)+&&+(goodFunction2)+%7C%7C+echo+"Oops,+that+didn't+work!"

echo+"Now+this+happens!"|9le3c|输出_1|le00|success1
success2
Now+this+happens!|6pc4n|示例_2|9qphm|functionThrowsErr(){
++#+this+function+returns+an+error
++ech+"halp+meh"
}

goodFunction2(){
++#+this+function+works+great
++echo+"success2"
++exit
}

(functionThrowsErr)+&&+(goodFunction2)+%7C%7C+echo+"Oops,+that+didn't+work!"

echo+"Now+this+happens!"|laa4|输出_2|5s6i8|main.sh:+line+3:+ech:+command+not+found
Oops,+that+didn't+work!
Now+this+happens!|3evgt|示例_3|5acd5|functionThrowsErr(){
++#+this+function+returns+an+error
++echo+"halp+meh"
++exit+1
}

goodFunction2(){
++#+this+function+works+great
++echo+"success2"
}

(functionThrowsErr)+&&+(goodFunction2)+%7C%7C+echo+"Oops,+that+didn't+work!"

echo+"Now+this+happens!"|fqo1h|输出_3|fqntf|halp+meh
Oops,+that+didn't+work!
Now+this+happens!|8o5gs|请注意，函数的顺序将影响输出。如果需要分别尝试和捕获这两个语句，请使用两个try+catch语句。|1oqvm|(functionThrowsErr)+%7C%7C+echo+"Oops,+functionThrowsErr+didn't+work!"
(goodFunction2)+%7C%7C+echo+"Oops,+good+function+is+bad"

echo+"Now+this+happens!"|bdvkv|输出|171ap|halp+meh
Oops,+functionThrowsErr+didn't+work!
success2
Now+this+happens!^0|0|0|H|6|0|H|4|0|0|0|0|0|0|0|0|0|0|0|0|0|0|0|0^^$0|$]|1|@$2|3|4|5|6|7|8|1L|9|@]|A|@]|B|$]]|$2|C|4|D|6|E|8|1M|9|@]|A|@]|B|$F|G]]|$2|H|4|I|6|7|8|1N|9|@$J|1O|K|1P|L|M]]|A|@]|B|$]]|$2|N|4|O|6|7|8|1Q|9|@$J|1R|K|1S|L|M]]|A|@]|B|$]]|$2|P|4|Q|6|7|8|1T|9|@]|A|@]|B|$]]|$2|R|4|S|6|E|8|1U|9|@]|A|@]|B|$F|G]]|$2|T|4|U|6|7|8|1V|9|@]|A|@]|B|$]]|$2|V|4|W|6|E|8|1W|9|@]|A|@]|B|$F|G]]|$2|X|4|Y|6|7|8|1X|9|@]|A|@]|B|$]]|$2|Z|4|10|6|E|8|1Y|9|@]|A|@]|B|$F|G]]|$2|11|4|12|6|7|8|1Z|9|@]|A|@]|B|$]]|$2|13|4|14|6|E|8|20|9|@]|A|@]|B|$F|G]]|$2|15|4|16|6|7|8|21|9|@]|A|@]|B|$]]|$2|17|4|18|6|E|8|22|9|@]|A|@]|B|$F|G]]|$2|19|4|1A|6|7|8|23|9|@]|A|@]|B|$]]|$2|1B|4|1C|6|E|8|24|9|@]|A|@]|B|$F|G]]|$2|1D|4|1E|6|7|8|25|9|@]|A|@]|B|$]]|$2|1F|4|1G|6|E|8|26|9|@]|A|@]|B|$F|G]]|$2|1H|4|1I|6|7|8|27|9|@]|A|@]|B|$]]|$2|1J|4|1K|6|E|8|28|9|@]|A|@]|B|$F|G]]]]

I found success in my script with this syntax:

<pre><code># Try, catch, finally
(echo "try this") &amp;&amp; (echo "and this") || echo "this is the catch statement!"

# this is the 'finally' statement
echo "finally this"
</code></pre>

If either try statement throws an error or ends with <code>exit 1</code>, then the interpreter moves on to the catch statement and then the finally statement.

If both try statements succeed (and/or end with <code>exit</code>), the interpreter will skip the catch statement and then run the finally statement.

Example_1:

<pre><code>goodFunction1(){
 # this function works great
 echo "success1"
}

goodFunction2(){
 # this function works great
 echo "success2"
 exit
}

(goodFunction1) &amp;&amp; (goodFunction2) || echo "Oops, that didn't work!"

echo "Now this happens!"
</code></pre>

Output_1

<pre><code>success1
success2
Now this happens!
</code></pre>

Example _2

<pre><code>functionThrowsErr(){
 # this function returns an error
 ech "halp meh"
}

goodFunction2(){
 # this function works great
 echo "success2"
 exit
}

(functionThrowsErr) &amp;&amp; (goodFunction2) || echo "Oops, that didn't work!"

echo "Now this happens!"
</code></pre>

Output_2

<pre><code>main.sh: line 3: ech: command not found
Oops, that didn't work!
Now this happens!
</code></pre>

Example_3

<pre><code>functionThrowsErr(){
 # this function returns an error
 echo "halp meh"
 exit 1
}

goodFunction2(){
 # this function works great
 echo "success2"
}

(functionThrowsErr) &amp;&amp; (goodFunction2) || echo "Oops, that didn't work!"

echo "Now this happens!"
</code></pre>

Output_3

<pre><code>halp meh
Oops, that didn't work!
Now this happens!
</code></pre>

Note that the order of the functions will affect output. If you need both statements to be tried and caught separately, use two try catch statements.

<pre><code>(functionThrowsErr) || echo "Oops, functionThrowsErr didn't work!"
(goodFunction2) || echo "Oops, good function is bad"

echo "Now this happens!"
</code></pre>

Output

<pre><code>halp meh
Oops, functionThrowsErr didn't work!
success2
Now this happens!
</code></pre>

Is there a linux bash command like the java try catch finally?
Or does the linux shell always go on?

<pre><code>try {
 `executeCommandWhichCanFail`
 mv output
} catch {
 mv log
} finally {
 rm tmp
}
</code></pre>

Writing try catch finally in shell

解释器

 有没有像java try catch finally这样的linux bash命令？还是linux shell一直在运行？ try {   `executeCommandWhichCanFail`   mv output} catch {    mv log} finally {    rm tmp}

问在shell中编写try catch finally
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