php - Warning: in_array() expects parameter 2 to be array -

i read php in_array manual , create code lines.

    $handle = fopen("/path/to/file", "a")  or die('cannot open file:');      $y= $command_name1.$steps1;     $x=trim(shell_exec("grep -ri -o '$y' /path/to/file "));     $z=array($x);     if (in_array($y,$z,false))     {             echo "thise 2 variables in file";             fclose($handle);     }      else {     //write thing on  file     } 

but gives above error. , want know is, can 2 variables($command_name1 , $steps1)adds , search through in_array ?.

$x isn't array, error.

take look in_array() definition , use.

as can see function signature

bool in_array ( mixed $needle , array $haystack [, bool $strict = false ] ) 

you need second argument (in case $haystack) array , not scalar value (whatever type is)