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diff --git a/launcher.c b/launcher.c
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+/*
+    Setuptools Script Launcher for Windows
+
+    This is a stub executable for Windows that functions somewhat like
+    Effbot's "exemaker", in that it runs a script with the same name but
+    a .py extension, using information from a #! line.  It differs in that
+    it spawns the actual Python executable, rather than attempting to
+    hook into the Python DLL.  This means that the script will run with
+    sys.executable set to the Python executable, where exemaker ends up with
+    sys.executable pointing to itself.  (Which means it won't work if you try
+    to run another Python process using sys.executable.)
+
+    To build/rebuild with mingw32, do this in the setuptools project directory:
+
+        gcc -mno-cygwin -O -s -o setuptools/launcher.exe launcher.c
+
+    It links to msvcrt.dll, but this shouldn't be a problem since it doesn't
+    actually run Python in the same process.  Note that using 'exec' instead
+    of 'spawn' doesn't work, because on Windows this leads to the Python
+    executable running in the *background*, attached to the same console
+    window, meaning you get a command prompt back *before* Python even finishes
+    starting.  So, we have to use spawnv() and wait for Python to exit before
+    continuing.  :(
+*/
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include "windows.h"
+
+int fail(char *format, char *data) {
+    /* Print error message to stderr and return 1 */
+    fprintf(stderr, format, data);
+    return 1;
+}
+
+
+
+
+
+int main(int argc, char **argv) {
+
+    char python[256];   /* python executable's filename*/
+    char script[256];   /* the script's filename */
+
+    HINSTANCE hPython;  /* DLL handle for python executable */
+    int scriptf;        /* file descriptor for script file */
+
+    char **newargs;     /* argument array for exec */
+    char *ptr, *end;    /* working pointers for string manipulation */
+
+    /* compute script name from our .exe name*/
+    GetModuleFileName(NULL, script, sizeof(script));
+    end = script + strlen(script);
+    while( end>script && *end != '.')
+        *end-- = '\0';
+    strcat(script, "py");
+
+    /* figure out the target python executable */
+
+    scriptf = open(script, O_RDONLY);
+    if (scriptf == -1) {
+        return fail("Cannot open %s\n", script);
+    }
+    end = python + read(scriptf, python, sizeof(python));
+    close(scriptf);
+
+    ptr = python-1;
+    while(++ptr < end && *ptr && *ptr!='\n' && *ptr!='\r') {
+        if (*ptr=='/')
+            *ptr='\\';  /* convert slashes to avoid LoadLibrary crashes... */
+    }
+
+    *ptr = '\0';
+    while (ptr>python && isspace(*ptr)) *ptr-- = '\0';  /* strip trailing sp */
+
+    if (strncmp(python, "#!", 2)) {
+        /* default to python.exe if no #! header */
+        strcpy(python, "#!python.exe");
+    }
+
+    /* At this point, the python buffer contains "#!pythonfilename" */
+
+    /* Using spawnv() can fail strangely if you e.g. find the Cygwin
+       Python, so we'll make sure Windows can find and load it */
+    hPython = LoadLibraryEx(python+2, NULL, LOAD_WITH_ALTERED_SEARCH_PATH);
+    if (!hPython) {
+        return fail("Cannot find Python executable %s\n", python+2);
+    }
+
+    /* And we'll use the absolute filename for spawnv */
+    GetModuleFileName(hPython, python, sizeof(python));
+
+    /* printf("Python executable: %s\n", python); */
+
+    /* Argument array needs to be argc+1 for args, plus 1 for null sentinel */
+    newargs = (char **)calloc(argc+2, sizeof(char *));
+    newargs[0] = python;
+    newargs[1] = script;
+    memcpy(newargs+2, argv+1, (argc-1)*sizeof(char *));
+    newargs[argc+1] = NULL;
+
+    /* printf("args 0: %s\nargs 1: %s\n", newargs[0], newargs[1]); */
+
+    return spawnv(P_WAIT, newargs[0], (const char * const *)(newargs));
+}
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