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Perlのバッククォートを使用して実行されたコマンドの戻り値を取得する

私はbashで次のことができます：

output=`command`
retcode=$?

Perlで同じことをする方法はありますか？このようなもの：

$output=`command`
$retcode=???
perlcommandreturn-code
22
petersohn

シェルの場合と同様に、$?変数を読み取ることができます。 man perlvarから

 $?      The status returned by the last pipe close, backtick ("``") command, successful call to wait() or waitpid(), or from the
               system() operator.  This is just the 16-bit status Word returned by the traditional Unix wait() system call (or else is made up
               to look like it).  Thus, the exit value of the subprocess is really ("$? >> 8"), and "$? & 127" gives which signal, if any, the
               process died from, and "$? & 128" reports whether there was a core dump.  (Mnemonic: similar to sh and ksh.)

               Additionally, if the "h_errno" variable is supported in C, its value is returned via $? if any "gethost*()" function fails.

               If you have installed a signal handler for "SIGCHLD", the value of $? will usually be wrong outside that handler.

               Inside an "END" subroutine $? contains the value that is going to be given to "exit()".  You can modify $? in an "END"
               subroutine to change the exit status of your program.  For example:

                   END {
                       $? = 1 if $? == 255;  # die would make it 255
                   }

               Under VMS, the pragma "use vmsish 'status'" makes $? reflect the actual VMS exit status, instead of the default emulation of
               POSIX status; see "$?" in perlvms for details.

               Also see "Error Indicators".
26
Matteo

そして、Perl 5.10以降、${^CHILD_ERROR_NATIVE}。

http://perldoc.Perl.org/Perl5100delta.html#New-internal-variables から：

${^CHILD_ERROR_NATIVE}

この変数は、最後のパイプクローズ、バックティックコマンド、wait（）またはwaitpid（）への正常な呼び出し、またはsystem（）オペレーターから返されたネイティブステータスを示します。詳細はperlvarを参照してください。

2
mivk