block.headerStart = 0;

        byte[] buf = new byte[256];
        buf[0] = 4; // wordCount for main block
        buf[1] = 0x66; // andxCommand
        ServerMessageBlock.writeInt2(50, buf, 3); // andxOffset
        ServerMessageBlock.writeInt2(20, buf, 9); // byteCount for main block

        // At offset 50, the implementation writes andx.wordCount (0) to buffer
        // Then reads byteCount at offset 51

然后它会使用你的 **FastAPI** 代码开启服务器，停在断点处，等等。

看起来可能是这样：

<img src="/img/tutorial/debugging/image01.png">

---

如果使用 Pycharm，你可以：

* 打开「运行」菜单。
* 选中「调试...」。
* 然后出现一个上下文菜单。
* 选择要调试的文件（本例中的 `main.py`）。

然后它会使用你的 **FastAPI** 代码开启服务器，停在断点处，等等。

看起来可能是这样：

 *
 * <p>The {@code Iterable} specification does not make it absolutely clear what should happen on a
 * second invocation, so implementors have made various choices, including:
 *
 * <ul>
 *   <li>returning the same iterator again
 *   <li>throwing an exception of some kind
 *   <li>or the usual, <i>robust</i> behavior, which all known {@link Collection} implementations
 *       have, of returning a new, independent iterator
 * </ul>
 *

private
val dirVersionPattern = "\\d+\\.\\d+(\\.\\d+)?(-\\w+)*(-\\d{14}[+-]\\d{4})?".toRegex()


val logger = Logging.getLogger("gradlebuild.cleanup")


/**
 * Removes state for versions that we're unlikely to ever need again, such as old snapshot versions.
 */
@Suppress("LoopWithTooManyJumpStatements")
fun FileSystemOperations.removeOldVersionsFromDir(dir: Directory, shouldDelete: Spec<GradleVersion>, dirPrefix: String = "", dirSuffix: String = "") {

                         * with node status so we need to check to make sure that
                         * the record type matches the question type and if not,
                         * loop around and try again.
                         */
                        if (response.received && request.questionType == response.recordType) {
                            return;
                        }

            sid.initContext("srv", mockCtx);

            // First accessor triggers resolution
            int t1 = sid.getType();
            assertEquals(t1, sid.getType()); // second call should not trigger again
            verify(mockResolver, times(1)).resolveSids(eq(mockCtx), eq("srv"), any(jcifs.SID[].class));
        }

        @Test

                    }
                }

                // TODO should this be inside the above check?
                // touch file so that this is not checked again until interval has passed
                if (file.exists()) {
                    file.setLastModified(System.currentTimeMillis());
                }
            }
        }

        try {

        // Keep the separate configuration checks
        assertEquals(
                "src/main/mdo/remote-resources.mdo",
                new MojoExecutionXPathContainer(executions.get(1)).getValue("configuration/models[1]/model"));
        assertEquals(
                "src/main/mdo/supplemental-model.mdo",
                new MojoExecutionXPathContainer(executions.get(4)).getValue("configuration/models[1]/model"));

It's relatively tightly coupled with relational databases (like MySQL or PostgreSQL), so, having a NoSQL database (like Couchbase, MongoDB, Cassandra, etc) as the main store engine is not very easy.

        assertEquals('C', stream.read());
        assertEquals('D', stream.read());

        // Reset to marked position
        stream.reset();

        // Should read from marked position again
        assertEquals('C', stream.read());
        assertEquals('D', stream.read());
    }

    public void test_toString_delegatesToUnderlying() {
        // Test that toString() delegates to underlying stream