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Operating System Utilities
- 
     int 
Py_FdIsInteractive(FILE *fp, const char *filename ) - 
     
Return true (nonzero) if the standard I/O file fp with name filename is deemed interactive. This is the case for files for which
isatty(fileno(fp))is true. If the global flagPy_InteractiveFlagis true, this function also returns true if the filename pointer is NULL or if the name is equal to one of the strings'<stdin>'or'???'. 
- 
     void 
PyOS_AfterFork( ) - 
     
Function to update some internal state after a process fork; this should be called in the new process if the Python interpreter will continue to be used. If a new executable is loaded into the new process, this function does not need to be called.
 
- 
     int 
PyOS_CheckStack( ) - 
     
Return true when the interpreter runs out of stack space. This is a reliable check, but is only available when
USE_STACKCHECKis defined (currently on Windows using the Microsoft Visual C++ compiler).USE_STACKCHECKwill be defined automatically; you should never change the definition in your own code. 
System Functions
These are utility functions that make functionality from the sys module accessible to C code. They all work with the current interpreter thread’s sys module’s dict, which is contained in the internal thread state structure.
- PyObject * 
PySys_GetObject(char *name ) - Return value: Borrowed reference.
     
Return the object name from the
sysmodule or NULL if it does not exist, without setting an exception. 
- 
     FILE * 
PySys_GetFile(char *name, FILE *def ) - 
     
Return the
FILE*associated with the object name in thesysmodule, or def if name is not in the module or is not associated with aFILE*. 
- 
     int 
PySys_SetObject(char *name, PyObject *v ) - 
     
Set name in the
sysmodule to v unless v is NULL, in which case name is deleted from the sys module. Returns0on success,-1on error. 
- 
     void 
PySys_ResetWarnOptions( ) - 
     
Reset
sys.warnoptionsto an empty list. 
- 
     void 
PySys_AddWarnOption(char *s ) - 
     
Append s to
sys.warnoptions. 
- 
     void 
PySys_SetPath(char *path ) - 
     
Set
sys.pathto a list object of paths found in path which should be a list of paths separated with the platform’s search path delimiter (:on Unix,;on Windows). 
- 
     void 
PySys_WriteStdout(const char *format, ... ) - 
     
Write the output string described by format to
sys.stdout. No exceptions are raised, even if truncation occurs (see below).format should limit the total size of the formatted output string to 1000 bytes or less – after 1000 bytes, the output string is truncated. In particular, this means that no unrestricted “%s” formats should occur; these should be limited using “%.<N>s” where <N> is a decimal number calculated so that <N> plus the maximum size of other formatted text does not exceed 1000 bytes. Also watch out for “%f”, which can print hundreds of digits for very large numbers.
If a problem occurs, or
sys.stdoutis unset, the formatted message is written to the real (C level) stdout. 
- 
     void 
PySys_WriteStderr(const char *format, ... ) - 
     
As above, but write to
sys.stderror stderr instead. 
Process Control
- 
     void 
Py_FatalError(const char *message ) - 
     
Print a fatal error message and kill the process. No cleanup is performed. This function should only be invoked when a condition is detected that would make it dangerous to continue using the Python interpreter; e.g., when the object administration appears to be corrupted. On Unix, the standard C library function
abort()is called which will attempt to produce acorefile. 
- 
     void 
Py_Exit(int status ) - 
     
Exit the current process. This calls
Py_Finalize()and then calls the standard C library functionexit(status). 
- 
     int 
Py_AtExit(void ( *func)() ) - 
     
Register a cleanup function to be called by
Py_Finalize(). The cleanup function will be called with no arguments and should return no value. At most 32 cleanup functions can be registered. When the registration is successful,Py_AtExit()returns0; on failure, it returns-1. The cleanup function registered last is called first. Each cleanup function will be called at most once. Since Python’s internal finalization will have completed before the cleanup function, no Python APIs should be called by func.