Patch #602345 by Neal Norwitz and me: add -B option and PYTHONDONTWRITEBYTECODE envvar to skip writing bytecode.
diff --git a/Doc/library/sys.rst b/Doc/library/sys.rst
index 24ce207..a98c5d4 100644
--- a/Doc/library/sys.rst
+++ b/Doc/library/sys.rst
@@ -507,6 +507,17 @@
when Python is started with the -3 option.
+.. data:: dont_write_bytecode
+
+ If this is true, Python won't try to write ``.pyc`` or ``.pyo`` files on the
+ import of source modules. This value is initially set to ``True`` or ``False``
+ depending on the ``-B`` command line option and the ``PYTHONDONTWRITEBYTECODE``
+ environment variable, but you can set it yourself to control bytecode file
+ generation.
+
+ .. versionadded:: 2.6
+
+
.. function:: setcheckinterval(interval)
Set the interpreter's "check interval". This integer value determines how often
diff --git a/Doc/using/cmdline.rst b/Doc/using/cmdline.rst
index 5f6bda5..b113c8f 100644
--- a/Doc/using/cmdline.rst
+++ b/Doc/using/cmdline.rst
@@ -145,6 +145,14 @@
Miscellaneous options
~~~~~~~~~~~~~~~~~~~~~
+.. cmdoption:: -B
+
+ If given, Python won't try to write ``.pyc`` or ``.pyo`` files on the
+ import of source modules. See also :envvar:`PYTHONDONTWRITEBYTECODE`.
+
+ .. versionadded:: 2.6
+
+
.. cmdoption:: -d
Turn on parser debugging output (for wizards only, depending on compilation
@@ -411,3 +419,10 @@
If this is set, Python ignores case in :keyword:`import` statements. This
only works on Windows.
+
+.. envvar:: PYTHONDONTWRITEBYTECODE
+
+ If given, Python won't try to write ``.pyc`` or ``.pyo`` files on the
+ import of source modules.
+
+ .. versionadded:: 2.6
diff --git a/Include/pydebug.h b/Include/pydebug.h
index 3282dc1..1d24853 100644
--- a/Include/pydebug.h
+++ b/Include/pydebug.h
@@ -17,6 +17,7 @@
PyAPI_DATA(int) Py_UnicodeFlag;
PyAPI_DATA(int) Py_IgnoreEnvironmentFlag;
PyAPI_DATA(int) Py_DivisionWarningFlag;
+PyAPI_DATA(int) Py_DontWriteBytecodeFlag;
/* _XXX Py_QnewFlag should go away in 3.0. It's true iff -Qnew is passed,
on the command line, and is used in 2.2 by ceval.c to make all "/" divisions
true divisions (which they will be in 3.0). */
diff --git a/Misc/NEWS b/Misc/NEWS
index 3896dd8..dbc0034 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -12,6 +12,10 @@
Core and builtins
-----------------
+- Patch #602345: Add -B command line option, PYTHONDONTWRITEBYTECODE envvar
+ and sys.dont_write_bytecode attribute. All these can be set to forbid Python
+ to attempt to write compiled bytecode files.
+
- Improve some exception messages when Windows fails to load an extension
module. Now we get for example '%1 is not a valid Win32 application' instead
of 'error code 193'.
diff --git a/Modules/main.c b/Modules/main.c
index 26f8780..71c9c59 100644
--- a/Modules/main.c
+++ b/Modules/main.c
@@ -40,7 +40,7 @@
static int orig_argc;
/* command line options */
-#define BASE_OPTS "3c:dEhim:OQ:StuUvVW:xX?"
+#define BASE_OPTS "3Bc:dEhim:OQ:StuUvVW:xX?"
#ifndef RISCOS
#define PROGRAM_OPTS BASE_OPTS
@@ -59,39 +59,42 @@
/* Long usage message, split into parts < 512 bytes */
static char *usage_1 = "\
Options and arguments (and corresponding environment variables):\n\
+-B : don't write .py[co] files on import; also PYTHONDONTWRITEBYTECODE=x\n\
-c cmd : program passed in as string (terminates option list)\n\
-d : debug output from parser; also PYTHONDEBUG=x\n\
-E : ignore environment variables (such as PYTHONPATH)\n\
-h : print this help message and exit (also --help)\n\
-i : inspect interactively after running script; forces a prompt even\n\
- if stdin does not appear to be a terminal; also PYTHONINSPECT=x\n\
";
static char *usage_2 = "\
+ if stdin does not appear to be a terminal; also PYTHONINSPECT=x\n\
-m mod : run library module as a script (terminates option list)\n\
-O : optimize generated bytecode slightly; also PYTHONOPTIMIZE=x\n\
-OO : remove doc-strings in addition to the -O optimizations\n\
-Q arg : division options: -Qold (default), -Qwarn, -Qwarnall, -Qnew\n\
-S : don't imply 'import site' on initialization\n\
-t : issue warnings about inconsistent tab usage (-tt: issue errors)\n\
--u : unbuffered binary stdout and stderr; also PYTHONUNBUFFERED=x\n\
";
static char *usage_3 = "\
+-u : unbuffered binary stdout and stderr; also PYTHONUNBUFFERED=x\n\
see man page for details on internal buffering relating to '-u'\n\
-v : verbose (trace import statements); also PYTHONVERBOSE=x\n\
can be supplied multiple times to increase verbosity\n\
-V : print the Python version number and exit (also --version)\n\
-W arg : warning control; arg is action:message:category:module:lineno\n\
-x : skip first line of source, allowing use of non-Unix forms of #!cmd\n\
+";
+static char *usage_4 = "\
-3 : warn about Python 3.x incompatibilities\n\
file : program read from script file\n\
- : program read from stdin (default; interactive mode if a tty)\n\
-";
-static char *usage_4 = "\
arg ...: arguments passed to program in sys.argv[1:]\n\n\
Other environment variables:\n\
PYTHONSTARTUP: file executed on interactive startup (no default)\n\
PYTHONPATH : '%c'-separated list of directories prefixed to the\n\
default module search path. The result is sys.path.\n\
+";
+static char *usage_5 = "\
PYTHONHOME : alternate <prefix> directory (or <prefix>%c<exec_prefix>).\n\
The default module search path uses %s.\n\
PYTHONCASEOK : ignore case in 'import' statements (Windows).\n\
@@ -110,7 +113,8 @@
fprintf(f, usage_1);
fprintf(f, usage_2);
fprintf(f, usage_3);
- fprintf(f, usage_4, DELIM, DELIM, PYTHONHOMEHELP);
+ fprintf(f, usage_4, DELIM);
+ fprintf(f, usage_5, DELIM, PYTHONHOMEHELP);
}
#if defined(__VMS)
if (exitcode == 0) {
@@ -337,6 +341,10 @@
Py_OptimizeFlag++;
break;
+ case 'B':
+ Py_DontWriteBytecodeFlag++;
+ break;
+
case 'S':
Py_NoSiteFlag++;
break;
diff --git a/Python/import.c b/Python/import.c
index e191bd5..8094f7d 100644
--- a/Python/import.c
+++ b/Python/import.c
@@ -950,8 +950,11 @@
if (Py_VerboseFlag)
PySys_WriteStderr("import %s # from %s\n",
name, pathname);
- if (cpathname)
- write_compiled_module(co, cpathname, mtime);
+ if (cpathname) {
+ PyObject *ro = PySys_GetObject("dont_write_bytecode");
+ if (ro == NULL || !PyObject_IsTrue(ro))
+ write_compiled_module(co, cpathname, mtime);
+ }
}
m = PyImport_ExecCodeModuleEx(name, (PyObject *)co, pathname);
Py_DECREF(co);
diff --git a/Python/pythonrun.c b/Python/pythonrun.c
index adae679..4939f54 100644
--- a/Python/pythonrun.c
+++ b/Python/pythonrun.c
@@ -72,6 +72,7 @@
int Py_InteractiveFlag; /* Needed by Py_FdIsInteractive() below */
int Py_InspectFlag; /* Needed to determine whether to exit at SystemError */
int Py_NoSiteFlag; /* Suppress 'import site' */
+int Py_DontWriteBytecodeFlag; /* Suppress writing bytecode files (*.py[co]) */
int Py_UseClassExceptionsFlag = 1; /* Needed by bltinmodule.c: deprecated */
int Py_FrozenFlag; /* Needed by getpath.c */
int Py_UnicodeFlag = 0; /* Needed by compile.c */
@@ -172,6 +173,8 @@
Py_VerboseFlag = add_flag(Py_VerboseFlag, p);
if ((p = Py_GETENV("PYTHONOPTIMIZE")) && *p != '\0')
Py_OptimizeFlag = add_flag(Py_OptimizeFlag, p);
+ if ((p = Py_GETENV("PYTHONDONTWRITEBYTECODE")) && *p != '\0')
+ Py_DontWriteBytecodeFlag = add_flag(Py_DontWriteBytecodeFlag, p);
interp = PyInterpreterState_New();
if (interp == NULL)
diff --git a/Python/sysmodule.c b/Python/sysmodule.c
index 2a6a8c3..bd551b5 100644
--- a/Python/sysmodule.c
+++ b/Python/sysmodule.c
@@ -1128,6 +1128,9 @@
v = Py_BuildValue("(ssz)", "CPython", branch, svn_revision);
PyDict_SetItemString(sysdict, "subversion", v);
Py_XDECREF(v);
+ PyDict_SetItemString(sysdict, "dont_write_bytecode",
+ v = PyBool_FromLong(Py_DontWriteBytecodeFlag));
+ Py_XDECREF(v);
/*
* These release level checks are mutually exclusive and cover
* the field, so don't get too fancy with the pre-processor!