diff --git a/numpy/f2py/crackfortran.py b/numpy/f2py/crackfortran.py
index 8d3fc27608bd..6df06aa3a386 100755
--- a/numpy/f2py/crackfortran.py
+++ b/numpy/f2py/crackfortran.py
@@ -3691,13 +3691,21 @@ def fix_usage(varname, value):
 post_processing_hooks.append(character_backward_compatibility_hook)
 
 
-if __name__ == "__main__":
+def main():
+    if len(sys.argv) < 2:
+        print(__doc__)
+        sys.exit(1)
+
     files = []
     funcs = []
     f = 1
     f2 = 0
     f3 = 0
+    strictf77 = 0
+    f77modulename = 0
+    skipemptyends = 0
     showblocklist = 0
+    pyffilename = None
     for l in sys.argv[1:]:
         if l == '':
             pass
@@ -3757,6 +3765,10 @@ def fix_usage(varname, value):
   statement).
 """, 0)
 
+    if len(files) == 0:
+        print('No input files specified, nothing to do')
+        sys.exit(0)
+
     postlist = crackfortran(files)
     if pyffilename:
         outmess('Writing fortran code to file %s\n' % repr(pyffilename), 0)
@@ -3765,3 +3777,6 @@ def fix_usage(varname, value):
             f.write(pyf)
     if showblocklist:
         show(postlist)
+
+if __name__ == "__main__":
+    main()
diff --git a/pyproject.toml b/pyproject.toml
index 2dc476f769da..4888784f2521 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -43,6 +43,7 @@ classifiers = [
 
 [project.scripts]
 f2py = 'numpy.f2py.f2py2e:main'
+crackfortran = 'numpy.f2py.crackfortran:main'
 
 [project.entry-points.array_api]
 numpy = 'numpy.array_api'