C 标准输入不起作用-6ren

C 标准输入不起作用

转载作者：塔克拉玛干更新时间：2023-11-03 01:01:40

我试图修复遗留代码中的一些错误。这是代码:

#include <stdio.h>
#include <string.h>
#include <pthread.h>
#include <sys/msg.h>

#include "libSvr.h"

#define CONEC 3
#define CONFIG 4

typedef struct {
    long type;
    int cmd;
    int id;
    char data[7000];
} msg;

typedef struct {
    int id[100];
    unsigned long ip[100];
    int type[100];
    char name[100][20];
    int num;
} conec;

typedef struct {
    char ip;
    char svr;
} param_cfg;

typedef struct {
    unsigned long my_ip;
    unsigned long svr_ip;
} tcp_cfg;

msg client, server;
conec conec_tab;

param_cfg param;
tcp_cfg setup;

void *Receive_MSG(void *arg) {
    int i;
    while (1) {
        if ( msgrcv(msgkey,&client,7008,2,0) != -1 ) {
            switch (client.cmd) {
                case CONEC:
                    memmove((char*)&conec_tab,client.data,sizeof(conec_tab));
                    printf("\n%d\n",conec_tab.num);
                    break;
                case CONFIG:
                    switch (conec_tab.type[client.id]) {
                        case 0:
                            memmove((char*)&param,&client.data[sizeof(param_cfg)],sizeof(param_cfg));
                            printf("------------PARAM Config------------\n");
                            printf("%c\n%c\n\n",param.ip,param.svr);
                            break;
                        case 1:
                            memmove((char*)&setup,client.data,sizeof(tcp_cfg));
                            printf("\n------------Setup------------\n");
                            printf("%s\n",Inet_ntoa(setup.my_ip));
                            break;
                    }
            }
        }
    }
}

void send_msg() {
    msgsnd(msgkey,&(server.type),7008,0);
}

void Process(char *command) {
    server.type = 1;

    if ( !strncmp(command,"text",8) ) {
        server.cmd = 1;
        send_text();
        send_msg();
    }
    else if ( !strncmp(command,"image",9) ) {
        server.cmd = 2;
        send_image();
        send_msg();
    }
    else
        printf("\nCommand not found.\n");
}

int main()
{
    int i;
    char cmd[100];
    msgkey=msgget(100,0);

    if ( msgkey == -1) {
        printf("ERROR msgkey!!");
        exit(1);
    }

    pthread_t receive;
    pthread_create(&receive,NULL,Receive_MSG,NULL);

    do {
        printf("Enter a command -> ");

        if (fgets(cmd,100,stdin) == NULL) {
            printf("error");
            exit(1);
        }

        cmd[strlen(cmd)-1]='\0';
        if ( (strcmp(cmd,"exit")) && (strcmp(cmd,"")) )
            Process(cmd);

    } while (strcmp(cmd,"exit"));

    return 0; 
}

libSvr.h代码:

#ifndef LIBSVR_H
#define LIBSVR_H

#pragma pack(push,1)
#pragma pack(1)


extern "C" void send_text();

extern "C" void send_image();


#pragma pack(pop)

#endif

线程 receive刚从队列 ID msgkey 中的另一个应用程序接收到一些消息并打印一些文本。

问题是当我进入 do while 循环时，我需要获得一些用户输入，fgets失败...当我打印错误(使用 errno )时，我看到这是一个错误的文件描述符错误( EBADF )。

Process function get 命令调用适当的函数，基本上将通过套接字发送一些数据。这些函数由 Process 调用来自用 C++ 编写的库 ( libSvr )，具有 C 外部函数。

我正在使用带有 gcc 4.7.2 的 ubuntu 12.10 机器。

我试图查看预处理器(使用 gcc -E)和 stdin 之后的代码仍显示为 stdin .我试图打印 fileno(stdin) 的输出它是 0(我在某处看到它是正确的值)然后我尝试调用 fgets这样:fgets(cmd,100,0) .但没有任何效果。

有人知道发生了什么事吗？

谢谢!

编辑:

包含所有代码。

我试过调用 gets() , scanf()和 read()并评论线程创建(pthread_create)但没有任何改变。

我运行了命令 strace -s2000 -etrace=open,close <MYPROGRAM>这是输出:

open("/mnt/hgfs/projects/tls/i686/sse2/cmov/libSvr.so.1", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
open("/mnt/hgfs/projects/tls/i686/sse2/libSvr.so.1", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
open("/mnt/hgfs/projects/tls/i686/cmov/libSvr.so.1", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
open("/mnt/hgfs/projects/tls/i686/libSvr.so.1", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
open("/mnt/hgfs/projects/tls/sse2/cmov/libSvr.so.1", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
open("/mnt/hgfs/projects/tls/sse2/libSvr.so.1", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
open("/mnt/hgfs/projects/tls/cmov/libSvr.so.1", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
open("/mnt/hgfs/projects/tls/libSvr.so.1", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
open("/mnt/hgfs/projects/i686/sse2/cmov/libSvr.so.1", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
open("/mnt/hgfs/projects/i686/sse2/libSvr.so.1", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
open("/mnt/hgfs/projects/i686/cmov/libSvr.so.1", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
open("/mnt/hgfs/projects/i686/libSvr.so.1", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
open("/mnt/hgfs/projects/sse2/cmov/libSvr.so.1", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
open("/mnt/hgfs/projects/sse2/libSvr.so.1", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
open("/mnt/hgfs/projects/cmov/libSvr.so.1", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
open("/mnt/hgfs/projects/libSvr.so.1", O_RDONLY|O_CLOEXEC) = 3
close(3)                                = 0
open("/mnt/hgfs/projects/libpthread.so.0", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
close(3)                                = 0
open("/lib/i386-linux-gnu/libpthread.so.0", O_RDONLY|O_CLOEXEC) = 3
close(3)                                = 0
open("/mnt/hgfs/projects/libc.so.6", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
open("/lib/i386-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
close(3)                                = 0
open("/mnt/hgfs/projects/libstdc++.so.6", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
open("/usr/lib/i386-linux-gnu/libstdc++.so.6", O_RDONLY|O_CLOEXEC) = 3
close(3)                                = 0
open("/mnt/hgfs/projects/libgcc_s.so.1", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
open("/lib/i386-linux-gnu/libgcc_s.so.1", O_RDONLY|O_CLOEXEC) = 3
close(3)                                = 0
open("/mnt/hgfs/projects/libm.so.6", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
open("/lib/i386-linux-gnu/libm.so.6", O_RDONLY|O_CLOEXEC) = 3
close(3)                                = 0
close(0)                                = 0
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)
close(0)                                = -1 EBADF (Bad file descriptor)

Enter a command -> 
errorEnter a command -> 
errorEnter a command -> 
errorEnter a command ->

因此，stdin文件描述符正在关闭，但现在我需要知道它在哪里关闭。

我现在正在研究一些 howto 和 strace 的手册页，因为我以前从未使用过它。

我们欢迎任何帮助和提示。

再次感谢!

最佳答案

我让你的代码运行了一些变化。我没有设法让 System V 的东西工作，但我让它读取命令而不会崩溃。

我认为您程序中 System V-stiff 的初始化是错误的，并且会产生未定义的行为。

所有 close(0)-s 可能来自某处的服务器线程，它不会因错误而从 while 循环中中断。

System V 的初始化(我不知道如何使用它，真的，只是阅读手册页)，我是这样做的:

    // msg_key is declared above the server-code (used by both) like `key_t msg_key`
    msg_key = ftok ("/home/atle/prog/test.c", 'A');
    if (msg_key == -1) {
            printf ("ftok error: %s\n", strerror(errno));
            exit(1);
    }
    msgkey = msgget(msg_key, IPC_CREAT);

    if ( msgkey == -1) {
            printf ("msgget error: %s\n", strerror(errno));
            exit(1);
    }

在服务器中，我是这样的:

    int msgkey_server = msgget(msg_key, 0);
    if ( msgkey_server == -1) {
            printf ("Server msgget error: %s\n", strerror(errno));
            exit(1);
    }

    while (1) {
            printf ("Server loop\n");
            if ( msgrcv(msgkey_server,&client,sizeof(client),0,0) == -1 ) {
                    printf ("Server read error: %s\n", strerror(errno));
                    exit(1);
            }
            else {
                   // MSG READ OK
            }

顺便说一句:

当你将一个结构传递给一个附加了它的大小的命令时，你应该像我在这里所做的那样始终使用 sizeof()，而不是手动写入大小(导致问题)。

额外顺便说一句:

您需要错误 header :

#include <errno.h>

关于C 标准输入不起作用，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/19437455/

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css - 输入[类型 ="button"]、输入[类型 ="submit"]、按钮 CSS 行为不正常
我正在努力让它发挥作用，但还是有些不对劲。我想用 CSS 设置提交按钮的样式以匹配我已有的按钮。风格: input[type="button"], input[type="submit"], b
Java数组通过nextInt()输入
import java.util.*;; public class selection { Scanner in=new Scanner(System.in); private
networking - 输入/输出带宽是否共享相同的网卡限制？
这可能是一个非常菜鸟的问题。假设我有一个带宽限制为 100MB/s 的网卡，那么输入/输出带宽是否有可能达到该限制同时 ?或者我会在任何时候遇到这个不等式:in bandwidth + out ba
scala - `this` 输入 Scala
看着这个问题，Fill immutable map with for loop upon creation ，我很好奇是什么this表示在 Map(1 -> this) . scala> Map(1
excel - 如何根据excel中的另一个单元格值限制单元格中的值输入/输入？
我有这样的东西一个乙问？是或否数字数字或零我想做的是: 如果 B1 = “Y”，则让用户在 B2 中输入一个数字。如果 B1 = “N”，则将 B2 中的值更改为零，并且不允许用户在
表格单元格内的 HTML 输入
我有一个包含许多列的表，我想添加 input标题单元格内的字段，但我希望输入适合根据正文内容的宽度。这是没有 input 的样子领域: 这就是 input 的样子领域: 可以看出，像“index”和
FTP 输入/输出文件夹名称最佳实践
关于为 FTP 客户端设置传出和传入文件夹，您遵循哪些最佳实践(如果有)？我们通常使用“outgoing”和“incoming”，但无论你如何表述方向，它都可以有两种解释方式，具体取决于名称相对于哪一
haskell - 输入 ‘where’ 解析错误
我正在尝试“求解”给定 d 的 Pell 方程:x^2 - d * y^2 = 1，或者至少我想得到最小的 x > 0 来求解方程。到目前为止，一切都很好。这是我的 Haskell 代码 minX :
python - VS代码在运行ctrl时移至下一行+输入
我是VS Code的新手，可以使用Ctrl + Enter将代码运行到python交互式窗口中。我希望光标自动移动到下一行，因此我可以逐行浏览代码。能做到吗？最佳答案如this blog pos
多维数组的 typescript 输入
我正在创建一个 bool 值矩阵/二维数组，并且我想为 dategrid 推断一种不仅仅是“ANY”的类型。 let yearRange = [2000,2001,2002,2003,2004]; l
python - “输入”两个具有最低复杂度的排序列表
我有两个排序的列表，例如 a = [1, 4, 7, 8] b = [1, 2, 3, 4, 5, 6] 我想知道a中的每个项目是否在b中。对于上面的示例，我想找到 a_in_b = [True, T
javascript - 输入/返回时指令语法错误
菜鸟警报这很奇怪 - 当我编写以下代码时，尝试在 AngularJS 中创建自定义指令: myModule.directive('myTab', function(){ console.lo
javascript - 单击显示文本字段(输入)
已关闭。此问题需要 debugging details 。目前不接受答案。编辑问题以包含 desired behavior, a specific problem or error, and the
godot - 输入 "Any"的正确方法
假设我正在使用 gdscript 静态类型，并且对于一个函数参数，我事先不知道我会得到什么。这就是 python 中 typing.Any 的作用。如何使用 gdscript 做到这一点？似乎 Va
javascript - 向图像添加字段(输入)
我使用 dropzone 上传多个图像，并且工作正常，直到我想为每个图像插入品牌和网址。我遇到的唯一问题是，当我要从输入字段获取值时，我会从服务器获取来自字段(品牌、网址)的未定义值，但如果我使用静

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