diff options
| -rw-r--r-- | Doc/lib/libos.tex | 6 | ||||
| -rw-r--r-- | Doc/lib/libpopen2.tex | 7 |
2 files changed, 13 insertions, 0 deletions
diff --git a/Doc/lib/libos.tex b/Doc/lib/libos.tex index 16f3690..1c3a584 100644 --- a/Doc/lib/libos.tex +++ b/Doc/lib/libos.tex @@ -315,6 +315,12 @@ specified, it specifies the buffer size for the I/O pipes. objects should be opened in binary or text mode. The default value for \var{mode} is \code{'t'}. +These methods do not make it possible to retrieve the return code from +the child processes. The only way to control the input and output +streams and also retrieve the return codes is to use the +\class{Popen3} and \class{Popen4} classes from the \refmodule{popen2} +module; these are only available on \UNIX. + \begin{funcdesc}{popen2}{cmd\optional{, mode\optional{, bufsize}}} Executes \var{cmd} as a sub-process. Returns the file objects \code{(\var{child_stdin}, \var{child_stdout})}. diff --git a/Doc/lib/libpopen2.tex b/Doc/lib/libpopen2.tex index add0af1..8cdf0f5 100644 --- a/Doc/lib/libpopen2.tex +++ b/Doc/lib/libpopen2.tex @@ -24,6 +24,13 @@ this is needed to determine whether the file objects should be opened in binary or text mode. The default value for \var{mode} is \code{'t'}. +The only way to retrieve the return codes for the child processes is +by using the \method{poll()} or \method{wait()} methods on the +\class{Popen3} and \class{Popen4} classes; these are only available on +\UNIX. This information is not available when using the +\function{popen2()}, \function{popen3()}, and \function{popen4()} +functions, or the equivalent functions in the \refmodule{os} module. + \begin{funcdesc}{popen2}{cmd\optional{, bufsize\optional{, mode}}} Executes \var{cmd} as a sub-process. Returns the file objects \code{(\var{child_stdout}, \var{child_stdin})}. |