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(python2.1-api.info)Very High Level Layer

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The Very High Level Layer
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The functions in this chapter will let you execute Python source code
given in a file or a buffer, but they will not let you interact in a
more detailed way with the interpreter.

Several of these functions accept a start symbol from the grammar as a
parameter.  The available start symbols are `Py_eval_input',
`Py_file_input', and `Py_single_input'.  These are described following
the functions which accept them as parameters.

Note also that several of these functions take `FILE*' parameters.  On
particular issue which needs to be handled carefully is that the `FILE'
structure for different C libraries can be different and incompatible.
Under Windows (at least), it is possible for dynamically linked
extensions to actually use different libraries, so care should be taken
that `FILE*' parameters are only passed to these functions if it is
certain that they were created by the same library that the Python
runtime is using.

`int Py_Main(int argc, char **argv)'
     The main program for the standard interpreter.  This is made
     available for programs which embed Python.  The ARGC and ARGV
     parameters should be prepared exactly as those which are passed to
     a C program's `main()' function.  It is important to note that the
     argument list may be modified (but the contents of the strings
     pointed to by the argument list are not).  The return value will
     be the integer passed to the `sys.exit()' function, `1' if the
     interpreter exits due to an exception, or `2' if the parameter
     list does not represent a valid Python command line.

`int PyRun_AnyFile(FILE *fp, char *filename)'
     If FP refers to a file associated with an interactive device
     (console or terminal input or UNIX pseudo-terminal), return the
     value of `PyRun_InteractiveLoop()', otherwise return the result of
     `PyRun_SimpleFile()'.  If FILENAME is `NULL', this function uses
     `"???"' as the filename.

`int PyRun_SimpleString(char *command)'
     Executes the Python source code from COMMAND in the `__main__'
     module.  If `__main__' does not already exist, it is created.
     Returns `0' on success or `-1' if an exception was raised.  If
     there was an error, there is no way to get the exception
     information.

`int PyRun_SimpleFile(FILE *fp, char *filename)'
     Similar to `PyRun_SimpleString()', but the Python source code is
     read from FP instead of an in-memory string.  FILENAME should be
     the name of the file.

`int PyRun_InteractiveOne(FILE *fp, char *filename)'
     Read and execute a single statement from a file associated with an
     interactive device.  If FILENAME is `NULL', `"???"' is used
     instead.  The user will be prompted using `sys.ps1' and `sys.ps2'.
     Returns `0' when the input was executed successfully, `-1' if
     there was an exception, or an error code from the `errcode.h'
     include file distributed as part of Python in case of a parse
     error.  (Note that `errcode.h' is not included by `Python.h', so
     must be included specifically if needed.)

`int PyRun_InteractiveLoop(FILE *fp, char *filename)'
     Read and execute statements from a file associated with an
     interactive device until `EOF' is reached.  If FILENAME is `NULL',
     `"???"' is used instead.  The user will be prompted using
     `sys.ps1' and `sys.ps2'.  Returns `0' at `EOF'.

`struct _node* PyParser_SimpleParseString(char *str, int start)'
     Parse Python source code from STR using the start token START.
     The result can be used to create a code object which can be
     evaluated efficiently.  This is useful if a code fragment must be
     evaluated many times.

`struct _node* PyParser_SimpleParseFile(FILE *fp, char *filename, int start)'
     Similar to `PyParser_SimpleParseString()', but the Python source
     code is read from FP instead of an in-memory string.  FILENAME
     should be the name of the file.

`PyObject* PyRun_String(char *str, int start, PyObject *globals, PyObject *locals)'
     Execute Python source code from STR in the context specified by
     the dictionaries GLOBALS and LOCALS.  The parameter START
     specifies the start token that should be used to parse the source
     code.

     Returns the result of executing the code as a Python object, or
     `NULL' if an exception was raised.

`PyObject* PyRun_File(FILE *fp, char *filename, int start, PyObject *globals, PyObject *locals)'
     Similar to `PyRun_String()', but the Python source code is read
     from FP instead of an in-memory string.  FILENAME should be the
     name of the file.

`PyObject* Py_CompileString(char *str, char *filename, int start)'
     Parse and compile the Python source code in STR, returning the
     resulting code object.  The start token is given by START; this
     can be used to constrain the code which can be compiled and should
     be `Py_eval_input', `Py_file_input', or `Py_single_input'.  The
     filename specified by FILENAME is used to construct the code
     object and may appear in tracebacks or `SyntaxError' exception
     messages.  This returns `NULL' if the code cannot be parsed or
     compiled.

`int Py_eval_input'
     The start symbol from the Python grammar for isolated expressions;
     for use with `Py_CompileString()' .

`int Py_file_input'
     The start symbol from the Python grammar for sequences of
     statements as read from a file or other source; for use with
     `Py_CompileString()' .  This is the symbol to use when compiling
     arbitrarily long Python source code.

`int Py_single_input'
     The start symbol from the Python grammar for a single statement;
     for use with `Py_CompileString()' .  This is the symbol used for
     the interactive interpreter loop.