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diff --git a/Doc/libpopen2.tex b/Doc/libpopen2.tex new file mode 100644 index 0000000..9e8a0ca --- /dev/null +++ b/Doc/libpopen2.tex @@ -0,0 +1,71 @@ +% This section was contributed by Drew Csillag +% <drew_csillag@geocities.com>, with some re-organization by Fred L. +% Drake, Jr. <fdrake@acm.org>. + +\section{Standard Module \module{popen2}} +\label{module-popen2} +\stmodindex{popen2} + +This module allows you to spawn processes and connect their +input/output/error pipes and obtain their return codes. + +The primary interface offered by this module is a pair of factory +functions: + +\begin{funcdesc}{popen2}{cmd\optional{, bufsize}} +Executes \var{cmd} as a sub-process. If \var{bufsize} is specified, +it specifies the buffer size for the I/O pipes. Returns +\code{(\var{child_stdout}, \var{child_stdin})}. +\end{funcdesc} + +\begin{funcdesc}{popen2}{cmd\optional{, bufsize}} +Executes \var{cmd} as a sub-process. If \var{bufsize} is specified, +it specifies the buffer size for the I/O pipes. Returns +\code{(\var{child_stdout}, \var{child_stdin}, \var{child_stderr})}. +\end{funcdesc} + +The class defining the objects returned by the factory functions is +also available: + +\begin{classdesc}{Popen3}{cmd\optional{, capturestderr\optional{, bufsize}}} +This class represents a child process. Normally, \class{Popen3} +instances are created using the factory functions described above. + +If not using one off the helper functions to create \class{Popen3} +objects, the parameter \var{cmd} is the shell command to execute in a +sub-process. The \var{capturestderr} flag, if true, specifies that +the object should capture standard error output of the child process. +The default is false. If the \var{bufsize} parameter is specified, it +specifies the size of the I/O buffers to/from the child process. +\end{classdesc} + + +\subsection{Popen3 Objects} +\label{popen3-objects} + +Instances of the \class{Popen3} class have the following methods: + +\begin{methoddesc}{poll}{} +Returns \code{-1} if child process hasn't completed yet, or its return +code otherwise. +\end{methoddesc} + +\begin{methoddesc}{wait}{} +Waits for and returns the return code of the child process. +\end{methoddesc} + + +The following attributes of \class{Popen3} objects are also available: + +\begin{datadesc}{fromchild} +A file object that provides output from the child process. +\end{datadesc} + +\begin{datadesc}{tochild} +A file object that provides input to the child process. +\end{datadesc} + +\begin{datadesc}{childerr} +Where the standard error from the child process goes is +\var{capturestderr} was true for the constructor, or \code{None}. +\end{datadesc} |