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如何分配结构的内存？(How to allocate memory of a struct?)

 我正在尝试为发送方结构分配内存并将其清零，但我不确定我是否正确执行此操作。 我正在尝试学习如何在我做这个项目时用C管理内存。 如何测试它以查看我设置的内存？ 我会尝试做什么，或者有更好的方法吗？  
typedef unsigned char uchar;

typedef struct {
    uchar Seq;
    uchar Ack;
    uchar Flags;
} Header;

#define FRAME_PAYLOAD_SIZE 50
struct Frame_t
{
    Header header;
    char data[FRAME_PAYLOAD_SIZE];
    uchar CRC;
};
typedef struct Frame_t Frame;

struct Sender
{
    uchar winSize;

    struct sendSlot {
        struct timeval timeout;
        Frame msg;
    } sendQ[5];
};


    initSend(Sender* sender) {
        sender->winSize = -1;

        char* send_buf = (char*) malloc(5 * sizeof(sender->sendQ[0]));
        memset(send_buf, 0, 5 * sizeof(sender->sendQ[0]));
        int i;
        for (i=0; i<sizeof(sender->sendQ)/sizeof(sender->sendQ[0]); i++) {
             memset(sender->sendQ[i].timeout, 0, sizeof(struct timeval));
            sender->sendQ = NULL;
         }
    }

I am trying to allocate memory and zero it out for the sender struct but I'm not sure if I am doing this correctly. I'm trying to learn how to manage memory in C while I am doing this project. How can I test it to see what I set the memory to? And will what I am trying to do work, or is there a better way of doing this?  
typedef unsigned char uchar;

typedef struct {
    uchar Seq;
    uchar Ack;
    uchar Flags;
} Header;

#define FRAME_PAYLOAD_SIZE 50
struct Frame_t
{
    Header header;
    char data[FRAME_PAYLOAD_SIZE];
    uchar CRC;
};
typedef struct Frame_t Frame;

struct Sender
{
    uchar winSize;

    struct sendSlot {
        struct timeval timeout;
        Frame msg;
    } sendQ[5];
};


    initSend(Sender* sender) {
        sender->winSize = -1;

        char* send_buf = (char*) malloc(5 * sizeof(sender->sendQ[0]));
        memset(send_buf, 0, 5 * sizeof(sender->sendQ[0]));
        int i;
        for (i=0; i<sizeof(sender->sendQ)/sizeof(sender->sendQ[0]); i++) {
             memset(sender->sendQ[i].timeout, 0, sizeof(struct timeval));
            sender->sendQ = NULL;
         }
    }

原文：https://stackoverflow.com/questions/33191801

更新时间：2022-06-21 21:06

最满意答案

 如果你需要一个隔离范围，那么有两个选项第一个选项是使用回调updateDisplayText如下所示：  
 JS  
app.controller('controller11', ['$scope', function ($scope) {
    $scope.displayText = "nature animal plant";
    $scope.updateDisplayText = function(text) {
        $scope.displayText = text;
    }
}]);
app.directive("blurredFocused", [function () {
    return {
        restrict: "A",
        priority: -1,
        scope: {
            updateDisplayText: "="
        },
        link: function (scope, ele, attrs) {
            ele.on("blur", function () {
                scope.$apply(function () {
                    scope.updateDisplayText("nature animal plant");
                });

            });
            ele.on("focus", function () {
                scope.$apply(function() {                   
                    scope.updateDisplayText("networkText");
                }
                );
            })
        }
    }
}]);
 
 HTML  
<div class="topSearchView">
    <input type="text"
               blurred-focused='databaseForm.connectionName' update-display-text="updateDisplayText" name="connectionName">
</div>
<div class="resultView">
    <ul>
        <li>
            <span>{{displayText}}</span>
        </li>
    </ul>
</div>
 
 第二种方法是将displayValue作为对象，如下所示：  
 JS  
app.controller('controller11', ['$scope', function ($scope) {
    $scope.displayText = {value: "nature animal plant"};
}]);
app.directive("blurredFocused", [function () {
    return {
        restrict: "A",
        priority: -1,
        scope: {
            displayText: "="
        },
        link: function (scope, ele, attrs) {
            ele.on("blur", function () {
                scope.$apply(function () {
                    scope.displayText.value = "nature animal plant";
                });

            });
            ele.on("focus", function () {
                scope.$apply(function() {                   
                    scope.displayText.value = "networkText";
                }
                );
            })
        }
    }
}]);
 
 HTML  
<div class="topSearchView">
    <input type="text"
           blurred-focused='databaseForm.connectionName' display-text="displayText" name="connectionName">
</div>
<div class="resultView">
    <ul>
        <li>
            <span>{{displayText.value}}</span>
        </li>
    </ul>
</div>

If you need an isolate scope, then there are two options The first option is to use callback updateDisplayText like this: 
JS 
app.controller('controller11', ['$scope', function ($scope) {
    $scope.displayText = "nature animal plant";
    $scope.updateDisplayText = function(text) {
        $scope.displayText = text;
    }
}]);
app.directive("blurredFocused", [function () {
    return {
        restrict: "A",
        priority: -1,
        scope: {
            updateDisplayText: "="
        },
        link: function (scope, ele, attrs) {
            ele.on("blur", function () {
                scope.$apply(function () {
                    scope.updateDisplayText("nature animal plant");
                });

            });
            ele.on("focus", function () {
                scope.$apply(function() {                   
                    scope.updateDisplayText("networkText");
                }
                );
            })
        }
    }
}]);
 
HTML 
<div class="topSearchView">
    <input type="text"
               blurred-focused='databaseForm.connectionName' update-display-text="updateDisplayText" name="connectionName">
</div>
<div class="resultView">
    <ul>
        <li>
            <span>{{displayText}}</span>
        </li>
    </ul>
</div>
 
The second approach would be to make displayValue as an object, like this: 
JS 
app.controller('controller11', ['$scope', function ($scope) {
    $scope.displayText = {value: "nature animal plant"};
}]);
app.directive("blurredFocused", [function () {
    return {
        restrict: "A",
        priority: -1,
        scope: {
            displayText: "="
        },
        link: function (scope, ele, attrs) {
            ele.on("blur", function () {
                scope.$apply(function () {
                    scope.displayText.value = "nature animal plant";
                });

            });
            ele.on("focus", function () {
                scope.$apply(function() {                   
                    scope.displayText.value = "networkText";
                }
                );
            })
        }
    }
}]);
 
HTML 
<div class="topSearchView">
    <input type="text"
           blurred-focused='databaseForm.connectionName' display-text="displayText" name="connectionName">
</div>
<div class="resultView">
    <ul>
        <li>
            <span>{{displayText.value}}</span>
        </li>
    </ul>
</div>

如何分配结构的内存？(How to allocate memory of a struct?)

最满意答案

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