PyObject *PyOS_FSPath(PyObject *path) Return the file system representation for path. If the object is a str or bytes object, then a new strong reference is returned. If the object implements the os.PathLike interface, then __fspath__() is returned as long as it is a str or bytes object. Otherwise TypeError is raised and NULL is returned.
Added in version 3.6.
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 PyConfig.interactive is non-zero, this function also returns true if the filename pointer is NULL or if the name is equal to one of the strings '<stdin>' or '???'.
This function must not be called before Python is initialized.
void PyOS_BeforeFork() Function to prepare some internal state before a process fork. This should be called before calling fork() or any similar function that clones the current process. Only available on systems where fork() is defined.
Warning
The C fork() call should only be made from the “main” thread (of the “main” interpreter). The same is true for PyOS_BeforeFork().
Added in version 3.7.
void PyOS_AfterFork_Parent() Function to update some internal state after a process fork. This should be called from the parent process after calling fork() or any similar function that clones the current process, regardless of whether process cloning was successful. Only available on systems where fork() is defined.
Warning
The C fork() call should only be made from the “main” thread (of the “main” interpreter). The same is true for PyOS_AfterFork_Parent().
Added in version 3.7.
void PyOS_AfterFork_Child() Function to update internal interpreter state after a process fork. This must be called from the child process after calling fork(), or any similar function that clones the current process, if there is any chance the process will call back into the Python interpreter. Only available on systems where fork() is defined.
Warning
The C fork() call should only be made from the “main” thread (of the “main” interpreter). The same is true for PyOS_AfterFork_Child().
Added in version 3.7.
See also
os.register_at_fork() allows registering custom Python functions to be called by PyOS_BeforeFork(), PyOS_AfterFork_Parent() and PyOS_AfterFork_Child().
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.
Deprecated since version 3.7: This function is superseded by PyOS_AfterFork_Child().
int PyOS_CheckStack() Return true when the interpreter runs out of stack space. This is a reliable check, but is only available when USE_STACKCHECK is defined (currently on certain versions of Windows using the Microsoft Visual C++ compiler). USE_STACKCHECK will be defined automatically; you should never change the definition in your own code.
typedef void (*PyOS_sighandler_t)(int) PyOS_sighandler_t PyOS_getsig(int i) Return the current signal handler for signal i. This is a thin wrapper around either sigaction() or signal(). Do not call those functions directly!
PyOS_sighandler_t PyOS_setsig(int i, PyOS_sighandler_t h) Set the signal handler for signal i to be h; return the old signal handler. This is a thin wrapper around either sigaction() or signal(). Do not call those functions directly!
int PyOS_InterruptOccurred(void) Check if a SIGINT signal has been received.
Returns 1 if a SIGINT has occurred and clears the signal flag, or 0 otherwise.
In most cases, you should prefer PyErr_CheckSignals() over this function. PyErr_CheckSignals() invokes the appropriate signal handlers for all pending signals, allowing Python code to handle the signal properly. This function only detects SIGINT and does not invoke any Python signal handlers.
This function is async-signal-safe and this function cannot fail. The caller must hold an attached thread state.
wchar_t *Py_DecodeLocale(const char *arg, size_t *size) Warning
This function should not be called directly: use the PyConfig API with the PyConfig_SetBytesString() function which ensures that Python is preinitialized.
This function must not be called before Python is preinitialized and so that the LC_CTYPE locale is properly configured: see the Py_PreInitialize() function.
Decode a byte string from the filesystem encoding and error handler. If the error handler is surrogateescape error handler, undecodable bytes are decoded as characters in range U+DC80..U+DCFF; and if a byte sequence can be decoded as a surrogate character, the bytes are escaped using the surrogateescape error handler instead of decoding them.
Return a pointer to a newly allocated wide character string, use PyMem_RawFree() to free the memory. If size is not NULL, write the number of wide characters excluding the null character into *size
Return NULL on decoding error or memory allocation error. If size is not NULL, *size is set to (size_t)-1 on memory error or set to (size_t)-2 on decoding error.
The filesystem encoding and error handler are selected by PyConfig_Read(): see filesystem_encoding and filesystem_errors members of PyConfig.
Decoding errors should never happen, unless there is a bug in the C library.
Use the Py_EncodeLocale() function to encode the character string back to a byte string.
See also
The PyUnicode_DecodeFSDefaultAndSize() and PyUnicode_DecodeLocaleAndSize() functions.
Added in version 3.5.
Changed in version 3.7: The function now uses the UTF-8 encoding in the Python UTF-8 Mode.
Changed in version 3.8: The function now uses the UTF-8 encoding on Windows if PyPreConfig.legacy_windows_fs_encoding is zero;
char *Py_EncodeLocale(const wchar_t *text, size_t *error_pos) Encode a wide character string to the filesystem encoding and error handler. If the error handler is surrogateescape error handler, surrogate characters in the range U+DC80..U+DCFF are converted to bytes 0x80..0xFF.
Return a pointer to a newly allocated byte string, use PyMem_Free() to free the memory. Return NULL on encoding error or memory allocation error.
If error_pos is not NULL, *error_pos is set to (size_t)-1 on success, or set to the index of the invalid character on encoding error.
The filesystem encoding and error handler are selected by PyConfig_Read(): see filesystem_encoding and filesystem_errors members of PyConfig.
Use the Py_DecodeLocale() function to decode the bytes string back to a wide character string.
Warning
This function must not be called before Python is preinitialized and so that the LC_CTYPE locale is properly configured: see the Py_PreInitialize() function.
See also
The PyUnicode_EncodeFSDefault() and PyUnicode_EncodeLocale() functions.
Added in version 3.5.
Changed in version 3.7: The function now uses the UTF-8 encoding in the Python UTF-8 Mode.
Changed in version 3.8: The function now uses the UTF-8 encoding on Windows if PyPreConfig.legacy_windows_fs_encoding is zero.
FILE *Py_fopen(PyObject *path, const char *mode) Similar to fopen(), but path is a Python object and an exception is set on error.
path must be a str object, a bytes object, or a path-like object.
On success, return the new file pointer. On error, set an exception and return NULL.
The file must be closed by Py_fclose() rather than calling directly fclose().
The file descriptor is created non-inheritable (PEP 446).
The caller must have an attached thread state.
Added in version 3.14.
int Py_fclose(FILE *file) Close a file that was opened by Py_fopen().
On success, return 0. On error, return EOF and errno is set to indicate the error. In either case, any further access (including another call to Py_fclose()) to the stream results in undefined behavior.
Added in version 3.14.
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Licensed under the PSF License.
https://docs.python.org/3.14/c-api/sys.html