Databases
StackOverflow2013
Postsdbo
POBizarre behavior of exec() in PHP
 

Note that there are some explanatory texts on larger screens.

plurals
  1. POBizarre behavior of exec() in PHP
    primarykey
    data
    text
    <p>I'm still a newbie in PHP, so forgive me if I'm missing something obvious here.</p> <p>So, I'm calling some back-end scripts which produce lines of text, and I thought I'd tinker around with <code>exec</code> to make sure it works correctly. Of course, in the (Linux) shell, an easy multiline output command is something like </p> <pre><code>echo a;echo b;echo c </code></pre> <p>which, of course, produces what one would expect:</p> <pre><code>a b c </code></pre> <p>So, why am I getting an extra "c" when I run <code>exec</code> below?</p> <p>input:</p> <pre><code>exec("echo a;echo b;echo c",$output,$return); echo("return: $return\n"); echo("count: ". count($output) . "\n"); foreach($output as $i) {print "$i\n";} var_dump($output); </code></pre> <p>output:</p> <pre><code>return: 0 count: 4 a b c c array(4) { [0]=&gt; string(1) "a" [1]=&gt; string(1) "b" [2]=&gt; string(1) "c" [3]=&gt; string(1) "c" } </code></pre> <p>Now, I know that <code>exec</code> returns the last line processed, but I didn't echo the return value of <code>exec</code>. And what makes this even more puzzling is that if I make the strings a bit more "random", it seems to work correctly:</p> <pre><code>jmaney&gt; php -r 'exec("echo asfd;echo asdfasf;echo grrrr",$output,$return);echo("return: $return\n");echo("count: ". count($output) . "\n");foreach($output as $i){print "$i\n";}var_dump($output);' return: 0 count: 3 asfd asdfasf grrrr array(3) { [0]=&gt; string(4) "asfd" [1]=&gt; string(7) "asdfasf" [2]=&gt; string(5) "grrrr" } </code></pre> <p>What am I missing here?</p> <p><strong>Edited to add:</strong> I'm running bash shell version 3.2.48, SUSE Enterprise Linux version 11, Linux Kernel version 2.6, and PHP version 5.2.12. </p>
    singulars
    1. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. PTQuestion
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PO
      singulars
      1. PTAnswer
    1. VO
      singulars
      1. POBizarre behavior of exec() in PHP
      1. This table or related slice is empty.
      1. VTUpMod
    2. VO
      singulars
      1. POBizarre behavior of exec() in PHP
      1. This table or related slice is empty.
      1. VTUpMod
    3. VO
      singulars
      1. POBizarre behavior of exec() in PHP
      1. This table or related slice is empty.
      1. VTUpMod
    1. COCannot reproduce. Running your exact code only produces 3 items in `$output`
      singulars
      1. POBizarre behavior of exec() in PHP
      1. USPhil
    2. COThat is...utterly bizarre.
      singulars
      1. POBizarre behavior of exec() in PHP
      1. This table or related slice is empty.
    3. COYour first code is outputting just what it should
      singulars
      1. POBizarre behavior of exec() in PHP
      1. USAndras Gyomrey
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload