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diff --git a/Doc/lib/libposix.tex b/Doc/lib/libposix.tex deleted file mode 100644 index aee6c0d..0000000 --- a/Doc/lib/libposix.tex +++ /dev/null @@ -1,97 +0,0 @@ -\section{\module{posix} --- - The most common \POSIX{} system calls} - -\declaremodule{builtin}{posix} - \platform{Unix} -\modulesynopsis{The most common \POSIX\ system calls (normally used - via module \refmodule{os}).} - - -This module provides access to operating system functionality that is -standardized by the C Standard and the \POSIX{} standard (a thinly -disguised \UNIX{} interface). - -\strong{Do not import this module directly.} Instead, import the -module \refmodule{os}, which provides a \emph{portable} version of this -interface. On \UNIX, the \refmodule{os} module provides a superset of -the \module{posix} interface. On non-\UNIX{} operating systems the -\module{posix} module is not available, but a subset is always -available through the \refmodule{os} interface. Once \refmodule{os} is -imported, there is \emph{no} performance penalty in using it instead -of \module{posix}. In addition, \refmodule{os}\refstmodindex{os} -provides some additional functionality, such as automatically calling -\function{putenv()} when an entry in \code{os.environ} is changed. - -The descriptions below are very terse; refer to the corresponding -\UNIX{} manual (or \POSIX{} documentation) entry for more information. -Arguments called \var{path} refer to a pathname given as a string. - -Errors are reported as exceptions; the usual exceptions are given for -type errors, while errors reported by the system calls raise -\exception{error} (a synonym for the standard exception -\exception{OSError}), described below. - - -\subsection{Large File Support \label{posix-large-files}} -\sectionauthor{Steve Clift}{clift@mail.anacapa.net} -\index{large files} -\index{file!large files} - - -Several operating systems (including AIX, HPUX, Irix and Solaris) -provide support for files that are larger than 2 Gb from a C -programming model where \ctype{int} and \ctype{long} are 32-bit -values. This is typically accomplished by defining the relevant size -and offset types as 64-bit values. Such files are sometimes referred -to as \dfn{large files}. - -Large file support is enabled in Python when the size of an -\ctype{off_t} is larger than a \ctype{long} and the \ctype{long long} -type is available and is at least as large as an \ctype{off_t}. Python -longs are then used to represent file sizes, offsets and other values -that can exceed the range of a Python int. It may be necessary to -configure and compile Python with certain compiler flags to enable -this mode. For example, it is enabled by default with recent versions -of Irix, but with Solaris 2.6 and 2.7 you need to do something like: - -\begin{verbatim} -CFLAGS="`getconf LFS_CFLAGS`" OPT="-g -O2 $CFLAGS" \ - ./configure -\end{verbatim} % $ <-- bow to font-lock - -On large-file-capable Linux systems, this might work: - -\begin{verbatim} -CFLAGS='-D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64' OPT="-g -O2 $CFLAGS" \ - ./configure -\end{verbatim} % $ <-- bow to font-lock - - -\subsection{Module Contents \label{posix-contents}} - - -Module \module{posix} defines the following data item: - -\begin{datadesc}{environ} -A dictionary representing the string environment at the time the -interpreter was started. For example, \code{environ['HOME']} is the -pathname of your home directory, equivalent to -\code{getenv("HOME")} in C. - -Modifying this dictionary does not affect the string environment -passed on by \function{execv()}, \function{popen()} or -\function{system()}; if you need to change the environment, pass -\code{environ} to \function{execve()} or add variable assignments and -export statements to the command string for \function{system()} or -\function{popen()}. - -\note{The \refmodule{os} module provides an alternate -implementation of \code{environ} which updates the environment on -modification. Note also that updating \code{os.environ} will render -this dictionary obsolete. Use of the \refmodule{os} module version of -this is recommended over direct access to the \module{posix} module.} -\end{datadesc} - -Additional contents of this module should only be accessed via the -\refmodule{os} module; refer to the documentation for that module for -further information. |