I'm trying to test out performing a simple TCP MODBUS read of a single register from a device emulator. When running the code it is showing a response of 0 bytes and I get the message "connection reset by peer". Any ideas as to why it's not working?

UPDATE, my request was incorrect, the correct working MODBUS TCP poll code is:

package main

import (

// TCP MODBUS client
func main() {
    conn, err := net.Dial("tcp", "")
    if err != nil {
    numRegs := 1
    # make a MODBUS TCP request (be careful, the format is different to MODBUS serial)
    request := []byte{0x00, 0x00, 0x00, 0x00, 0x00, 0x06, 0x01, 0x03, 0x00, 0x01, 0x00, 0x01}
    n, err := conn.Write(request)
    if err != nil {
    expectedResponseLen := 5 + 2 * numRegs
    response := make([]byte, expectedResponseLen)
    n, err = conn.Read(response)
    if err != nil {
    for i := 0; i < n; i++ {
        fmt.Printf("%02x ", response[i])
dsorecdf78171 谢谢汤姆,我的请求格式错误,正确的代码在上面。
6 年多之前 回复
duanjue9296 由对等方重置连接通常意味着客户端接受了连接但在收到您的请求后挂断了。也许请求有问题?(此外,我认为您打算使用fmt.Fprint)
6 年多之前 回复
dongle19863 这似乎确实是与网络相关的问题,而不是您的代码有问题。对等方重置连接可能是由于没有人在该端口上侦听或服务由于某种原因未应答您的呼叫而导致的。你检查了吗?
6 年多之前 回复


我原本以为 fmt.Fprintf </ code>可能正在更改请求数据,但此示例似乎可以正常运行。</ p>

但是,我仍然 建议使用较低级别的 Write / Read </ code>(而不是 fmt.Fprintf / ioutil.ReadAll </ code>):</ p>

  req:=  [] byte {0x01,0x03,0x00,0x01,0x00,0x01,0xd5,0xca} 

n,err:= conn.Write(req)

if err!= nil {
fmt.Println(“ 写入错误:“,err)


rsp:= make([] byte,64 )

n,err = conn.Read(rsp)

fmt.Printf(“响应中收到%d个字节:%#v”,n,rsp [:n])

if err!= nil {
</ code> </ pre>
</ div>



Originally I thought that fmt.Fprintf may be changing the request data on the way out, but this example seems to work OK.

However, I would still recommend using the lower-level Write/Read instead of fmt.Fprintf/ioutil.ReadAll:

req := []byte { 0x01, 0x03, 0x00, 0x01, 0x00, 0x01, 0xd5, 0xca }

n, err := conn.Write(req)

if err != nil {
    fmt.Println("write error:", err)

fmt.Printf("wrote %d bytes for request: %#v", n, req)

rsp := make([]byte, 64)

n, err = conn.Read(rsp)

fmt.Printf("received %d bytes in response: %#v", n, rsp[:n])

if err != nil {
    fmt.Println("read error:", err)

douyongdao4046 我重新编写了代码以使用con.Write。 我遇到的主要问题是我的请求数据包格式错误。 我已经使用工作版本更新了帖子中的代码。
6 年多之前 回复
Csdn user default icon

<div class="post-text" itemprop="text"> <p>My code: </p> <pre><code>func getSourceUrl(url string) (string, error) { resp, err := http.Get(url) if err != nil { fmt.Println("Error getSourceUrl: ") return "", err } defer resp.Body.Close() body := resp.Body // time = 0 sourcePage, err := ioutil.ReadAll(body) // time &gt; 5 minutes return string(sourcePage), err } </code></pre> <p>I have a website link with a source of around&gt; 100000 lines. Using ioutil.ReadAll made me get very long (about&gt; 5 minutes for 1 link). Is there a way to get Source website faster? Thank you!</p> </div>


<div class="post-text" itemprop="text"> <p>For some reason, I cannot seem to get <code>ioutil.ReadAll(res.Body)</code>, where <code>res</code> is the <code>*http.Response</code> returned by <code>res, err := hc.Do(redirectRequest)</code> (for <code>hc http.Client</code>, <code>redirectRequest *http.Request</code>). </p> <p><strong>Testing strategy thus far</strong></p> <p><em>Any time</em> I see <code>hc.Do</code> or <code>http.Request</code> in the SUT, my instinct is to spin up a fake server and point the appropriate application states to it. Such a server, for this test, looks like this : </p> <pre><code>badServer := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) { // some stuff w.Write([some bad bytes]) })) defer badServer.Close() </code></pre> <p>I don't seem to have a way to control <code>res.Body</code>, which is literally the only thing keeping me from 100% test completion against the func this is all in. </p> <p>I tried, in the <code>errorThrowingServer</code>'s handler func, setting <code>r.Body</code> to a stub <code>io.ReadCloser</code> that throws an error when <code>Read()</code> is called, but that doesn't effect <code>res</code>. </p> </div>


<div class="post-text" itemprop="text"> <pre><code>tr := &amp;http.Transport{ TLSClientConfig: &amp;tls.Config{InsecureSkipVerify: true}, } client := &amp;http.Client{Transport: tr} response, err := client.Get(link) if err != nil { fmt.Println(err) } defer response.Body.Close() //block forever at the next line content, _ = ioutil.ReadAll(response.Body) </code></pre> <p>The above is my code to read content from a webpage which resides in a loop. I found sometimes the line <code>ioutil.ReadAll(response.Body)</code> will block forever. This happens randomly, however, it almost always happens on this webpage: <code>http://xkcd.com/55</code> . It's very interesting that when I do <code>curl http://xkcd.com/55</code>, it returns nothing, however, <code>wget http://xkcd.com/55</code> returns the whole webpage.</p> </div>


<div class="post-text" itemprop="text"> <p>I'm currently learning Golang (and so far I love it). But unfortunately, I've been stuck for a couple hours and I don't seem to find any solution to my problem on Google.</p> <p>So here's my problem. I have this piece of code (from a tutorial) :</p> <pre><code>func main() { var s SitemapIndex resp, _ := http.Get("https://www.washingtonpost.com/news-sitemaps/index.xml") bytes, _ := ioutil.ReadAll(resp.Body) resp.Body.Close() xml.Unmarshal(bytes, &amp;s) for _, Location := range s.Locations { resp, _ := http.Get(Location) ioutil.ReadAll(resp.Body) } } </code></pre> <p>I know, my code is incomplete but that's because I deleted the parts that were not causing the problem to make it more readable on Stackoverflow.</p> <p>So when I get the content of <code>Location</code> and try to process the data with <code>ioutil.ReadAll()</code> I get this error mentioning a pointer :</p> <pre><code>panic: runtime error: invalid memory address or nil pointer dereference [signal SIGSEGV: segmentation violation code=0x1 addr=0x40 pc=0x1210a69] goroutine 1 [running]: main.main() /Users/tom/Developer/Go/src/news/index.go:23 +0x159 exit status 2 </code></pre> <p>I really don't understand this error, no matter how much I look into it. I tried to pull the error from <code>ioutil.ReadAll(resp.Body)</code> by doing <code>_, e := ioutil.ReadAll(resp.Body)</code> and then printing <code>e</code>, but doing that throws <em>another</em> error...</p> <p>I read somewhere that it can be because the body returned to me has errors, but it's working fine in the tutorial.</p> <p>Hopefully you guys will have a solution for me. Thanks.</p> <p>EDIT : Here are the structs I have defined :</p> <pre><code>type SitemapIndex struct { Locations []string `xml:"sitemap&gt;loc"` } type News struct { Titles []string `xml:"url&gt;news&gt;title"` Keywords []string `xml:"url&gt;news&gt;keywords"` Locations []string `xml:"url&gt;loc"` } type NewsMap struct { Keyword string Location string } </code></pre> </div>

golang不能将bufio.ReadString {}与ioutil.ReadFile()一起使用

<div class="post-text" itemprop="text"> <p>If I try to read the file name through the terminal go can't seem to find it. But if I hard code it everything works out fine? this isn't a problem with writing out.</p> <p>This code:</p> <pre><code>package main import ( "bufio" "fmt" "io/ioutil" "os") func check(e error) { if e != nil { panic(e) } } func getUserInput(message string) (text string){ reader := bufio.NewReader(os.Stdin) fmt.Println(message) text, err := reader.ReadString(' ') check(err) return text } func main() { input := getUserInput("File to open?") fmt.Println(input) dat, err := ioutil.ReadFile(input) check(err) fmt.Print("% x ", dat) input = getUserInput("File to write?") d1 := []byte(dat) e := ioutil.WriteFile(input, d1, 0644) check(e) } </code></pre> <p>Yields:</p> <pre><code>panic: open a.jpg : no such file or directory goroutine 1 [running]: runtime.panic(0x4a36c0, 0xc21001d2a0) /usr/lib/go/src/pkg/runtime/panic.c:266 +0xb6 main.check(0x7fdcd2e07088, 0xc21001d2a0) /home/matt/Dropbox/CSE3320/fs_GO/fs.go:17 +0x4f main.main() /home/matt/Dropbox/CSE3320/fs_GO/fs.go:35 +0x13e exit status 2 </code></pre> <p>yet this code:</p> <pre><code>package main import ( "bufio" "fmt" "io/ioutil" "os") func check(e error) { if e != nil { panic(e) } } func getUserInput(message string) (text string){ reader := bufio.NewReader(os.Stdin) fmt.Println(message) text, err := reader.ReadString(' ') check(err) return text } func main() { //input := getUserInput("File to open?") //fmt.Println(input) dat, err := ioutil.ReadFile("a.jpg") check(err) //fmt.Print("% x ", dat) input := getUserInput("File to write?") d1 := []byte(dat) e := ioutil.WriteFile(input, d1, 0644) check(e) } </code></pre> <p><a href="https://i.stack.imgur.com/QwuOb.png" rel="nofollow noreferrer">Appears to work just fine</a></p> <p>When running the first code without checking for error a blank new file is created. Yet the second run works perfectly fine even writing the file with the same function to get the new file name. </p> <p>I'm completely lost as to what I'm doing wrong here. Here is my version info if that helps let me know what else you need.</p> <p><code>go version</code> gives me <code>go version go1.2.1 linux/amd64</code>.</p> </div>


<div class="post-text" itemprop="text"> <pre><code>http://plg1.yumenetworks.com/dynamic_preroll_playlist.vast2xml?domain=2210cZDclAme </code></pre> <p>when I call the link above from the server using <code>http.Get</code> I get this response, an empty XML:</p> <pre><code>&lt;?xml version="1.0" encoding="UTF-8"?&gt; &lt;VAST version="2.0"&gt; &lt;/VAST&gt; </code></pre> <p>But when I call it from the browser it responsed with a valid XML,also when I called the link from a local server it works.</p> <pre><code>func getXmlVast(url string) (string, error) { resp, err := http.Get(url) if err != nil { return "", err } defer resp.Body.Close() // read xml http response xmlData, err := ioutil.ReadAll(resp.Body) if err != nil { return "", err } return string(xmlData), nil } </code></pre> <p>Does anyone have an idea.</p> <p>Thank you in advance </p> </div>


<div class="post-text" itemprop="text"> <p>I have the following function:</p> <pre><code>func ObtainTranslationStringsFile(path string) ([]string, error) { if contents, err := ioutil.ReadFile(path); err != nil { return ObtainTranslationStrings(string(contents)) } else { return nil, err } } </code></pre> <p>I need to mock ioutil.ReadFile, but I'm not sure how to do it. Is it possible?</p> </div>


<div class="post-text" itemprop="text"> <p>I am running a program in Go which sends data continuously after reading a file <code>/proc/stat</code>. Using <code>ioutil.ReadFile("/proc/stat")</code> After running for about 14 hrs i got err: <code>too many files open /proc/stat</code> Click <a href="http://play.golang.org/p/iiqLOhEgHv" rel="nofollow noreferrer">here</a> for snippet of code.</p> <p>I doubt that defer <code>f.Close</code> is ignored by Go sometimes or it is skipping it.</p> <hr> <p>The snippet of code (in case play.golang.org dies sooner than stackoverflow.com):</p> <pre><code>package main import ("fmt";"io/ioutil") func main() { for { fmt.Println("Hello, playground") fData,err := ioutil.ReadFile("/proc/stat") if err != nil { fmt.Println("Err is ",err) } fmt.Println("FileData",string(fData)) } } </code></pre> </div>


<div class="post-text" itemprop="text"> <p>Programming with Go, I noticed that the function ioutil.WriteFile (from the ioutil library) needs some numbers as arguments. What do these numbers mean?</p> <p>Example:</p> <p><code>ioutil.WriteFile(file_to_write, []byte(string_to_write), 0644) // what 0644 stands for?</code></p> </div>


<div class="post-text" itemprop="text"> <p>I encountered a strange behavior of the conn.Read: let's presume that I have a couple of functions for testing net.Conn:</p> <pre><code>package example import ( "io" "log" "net" "os" "time" ) func CheckConn(conn net.Conn) (net.Conn, error) { conn.SetReadDeadline(time.Now()) var one = []byte{} _, err := conn.Read(one) if err != nil { log.Println("Net err: ", err) } if err == io.EOF { return conn, err } var zero time.Time conn.SetReadDeadline(zero) return conn, nil } func CheckConnWithTimeout(conn net.Conn) (net.Conn, error) { ch := make(chan bool, 1) defer func() { ch &lt;- true }() go func() { select { case &lt;-ch: case &lt;-time.After(1 * time.Second): log.Println("It works too long") os.Exit(1) } }() return CheckConn(conn) } </code></pre> <p>And I want to implement tests for it, lets start with this one:</p> <pre><code>package example import ( "io" "net" "testing" ) func TestClosedConn(t *testing.T) { server, client := net.Pipe() client.Close() defer server.Close() _, err := CheckConn(server) if err != io.EOF { t.Errorf("Not equal: Expected: %v actual: %v", io.EOF, err) } } </code></pre> <p>this works pretty well, we will receive io.EOF from CheckConn function, lets add one more test:</p> <pre><code>func TestClosedConnAfterWrite(t *testing.T) { server, client := net.Pipe() go func() { client.Write([]byte{0xb}) }() client.Close() defer server.Close() _, err := CheckConn(server) err = nil if err != io.EOF { t.Errorf("Not equal: Expected: %v actual: %v", io.EOF, err) } } </code></pre> <p>looks like the first test, but we wrote to the client before(?) it was closed.</p> <p>And this will not pass!</p> <p>conn.Read will return &amp;errors.errorString{s:"EOF"}, instead of io.EOF, so CheckConn will return error == nil,</p> <p>It looks so weird!</p> <p>But let's continue the tests, now I want to check unclosed connections:</p> <pre><code>func TestActiveConn(t *testing.T) { server, client := net.Pipe() defer client.Close() defer server.Close() _, err := CheckConnWithTimeout(server) if err != nil { t.Errorf("Not equal: Expected: %v actual: %v", nil, err) } } </code></pre> <p>I think you noticed that I use the function with a timeout just because SetReadDeadline will not work in this case(I have no idea why!)</p> <p>So what is going wrong in last two test cases? Is there a normal way to test the connection? Why SetReadDeadline is not working in this case?</p> </div>


<div class="post-text" itemprop="text"> <p>I am trying to make a program which writes at provided offsets in the file, like i can start writing from 20th offset etc.</p> <p>here is one of sample code i was using as reference</p> <pre><code>package main import ( "fmt" "io/ioutil" "os" ) const ( filename = "sample.txt" start_data = "12345" ) func printContents() { data, err := ioutil.ReadFile(filename) if err != nil { panic(err) } fmt.Println("CONTENTS:", string(data)) } func main() { err := ioutil.WriteFile(filename, []byte(start_data), 0644) if err != nil { panic(err) } printContents() f, err := os.OpenFile(filename, os.O_RDWR, 0644) if err != nil { panic(err) } defer f.Close() if _, err := f.Seek(20, 0); err != nil { panic(err) } if _, err := f.WriteAt([]byte("A"), 15); err != nil { panic(err) } printContents() } </code></pre> <p>But i am always getting the same file content which is beginning from start like</p> <pre><code>12345A </code></pre> <p>I tried changing the <strong>seek</strong> values to (0,0) and (20,0) and (10,1) randomly which results in same output</p> <p>Also i tried changing <strong>WriteAt offset</strong> to other offset like 10, 20 but this also resulted in same.</p> <p>I want to get a solution so that i can write at any specified position in file, suggest me what is wrong in this code.</p> </div>

Golang错误ioutil.ReadDir()列出CIFS共享上的文件? 还是做错了什么?

<div class="post-text" itemprop="text"> <p>Trying to get a list of filenames from a directory that is mounted to a CIFS file system. When there are a certain number of files (&gt;55) that are in a sequence, i.e. 00000.xxx through 00299.xxx, some files are missing from the list (e.g. file 00055.xxx might not be there). Doesn't matter the size of the files. They can be zero sized. Using the same code from a local file system works just fine. The missing file(s) seem to be consistent with the number of files in the directory (e.g. 56 files in the directory might be missing file 21 always, whereas 300 files might be missing 55, 81, 137). No errors are returned in the below programs.</p> <p>This is running on CentOS 7.4.</p> <p>Reduced the golang program to two different methods (both fail):</p> <p>Method 1:</p> <pre><code>package main import "os" import "fmt" import "io/ioutil" func main() { directory := os.Args[1] files, readDirError := ioutil.ReadDir(directory) if readDirError != nil { fmt.Printf("Error in readDir ") fmt.Println(readDirError) fmt.Println(" ") } for x, f := range files { fmt.Printf("%d =&gt; %s ", x, f.Name()) } } </code></pre> <p>Method #2</p> <pre><code>package main import "os" import "fmt" func main() { dir, readDirError := os.Open(os.Args[1]) defer dir.Close() if readDirError != nil { fmt.Printf("Error in readDir ") fmt.Println(readDirError) fmt.Println(" ") } fi, err := dir.Stat() if err != nil { fmt.Println(err) return } if fi.IsDir() { fis, err := dir.Readdir(-1) if err != nil { fmt.Println(err) return } for _, fileinfo := range fis { fmt.Printf("%s ", fileinfo.Name()) } } } </code></pre> <p>Created a C program that did the same thing, and this works every time, i.e. it lists all the files in the directory. So, it doesn't seem to be a problem with getting all the information from the file system.</p> <pre><code>#include &lt;dirent.h&gt; #include &lt;stdio.h&gt; int main(int c, char **argv) { DIR *d; struct dirent *dir; d = opendir(argv[1]); if (d) { while ((dir = readdir(d)) != NULL) { printf("%s ", dir-&gt;d_name); } closedir(d); } return(0); } </code></pre> <p>Any clue on what the problem might be? I'm thinking, at this point, that we may need to wrap a C function to get the proper list.</p> <p>By the way, the files in the directory all have the same permissions, none are symbolic or hard links, everything looks normal from the ls -l command on a terminal window.</p> </div>


<div class="post-text" itemprop="text"> <p>I have a json file (themes/snow/theme.json)</p> <pre><code>{ Name:'snow', Bgimage:'background.jpg', Width:600, Height:400, Itemrotation:'20,40', Text:{ Fontsize:12, Color:'#ff00ff', Fontfamily:'verdana', Bottommargin:20 }, Decoration:[ { Path:'abc.jpg', X:2, Y:4, Rotation:0 }, { Path:'def.png', X:4, Y:22, Rotation:10 } ] } </code></pre> <p>And I have a file that parse the json data</p> <pre><code>package main import ( "fmt" "os" "encoding/json" "io/ioutil" "log" ) const themeDirectory = "themes" const themeJsonFile = "theme.json" type TextInfo struct { Fontsize int Color string Fontfamily string Bottommargin int } type DecoInfo struct { Path string X int Y int Rotation int } type ThemeInfo struct { Name string Bgimage string Width int Height int Itemrotation string Text textInfo Decoration []decoInfo } func main() { var tinfo = parseTheme("snow") //use tinfo to build graphics } func parseTheme(themename string) themeInfo { abspath, _ := os.Getwd() filename := abspath + "/" + themeDirectory + "/" + themename + "/" + themeJsonFile //Check this file exists if _, error := os.Stat(filename); error != nil { if os.IsNotExist(error) { log.Fatal(filename + " does not exist") os.Exit(1) } } filebyte, error := ioutil.ReadFile(filename) if error != nil { log.Fatal("Could not read file " + filename + " to parse") os.Exit(1) } var t themeInfo json.Unmarshal(filebyte, &amp;t) fmt.Println(t) return t } </code></pre> <p>You can see I have 2 lines before the end</p> <pre><code> fmt.Println(t) </code></pre> <p>I am not sure why does it print </p> <pre><code>{ 0 0 {0 0} []} </code></pre> <p>I expect it should return me themeInfo in a usable way, so that I can use it for further processing.What am I doing wrong here?</p> </div>


<div class="post-text" itemprop="text"> <p>注意: 为了简单起见,省略了所有错误处理代码。</p> <p>在 Golang,我尝试使用下面的代码从 ahttp.Request.Body 中读取来自 POST 请求:</p> <pre><code>func readBody(req *http.Request) string { bytes, _ := httputils.DumpRequestOut(req, true) return string(bytes) } </code></pre> <p>它显示了一个非零的 Content-Length,但是没有返回内容: </p> <pre><code>ContentLength=413 with Body length 0 </code></pre> <p>我也试过下面的代码,同样不行:</p> <pre><code>func readBody(req *http.Request) string { bytes, _ := ioutil.ReadAll(req.Body) return string(bytes) } </code></pre> <p>它返回了一个空字符串,在 google 搜索之后,我发现了一个关于这个问题的博客:<a href="https://medium.com/@xoen/golang-read-from-an-io-readwriter-without-loosing-its-content-2c6911805361" rel="nofollow">Golang: Read from an io.ReadWriter without losing its content</a>。我试图遵循这个模式,但还是没有成功:</p> <pre><code>func readBody(req *http.Request) string { bodyBytes, _ := ioutil.ReadAll(req.Body) // Restore the io.ReadCloser to its original state req.Body = ioutil.NopCloser(bytes.NewBuffer(bodyBytes)) // Use the content return string(bodyBytes) } </code></pre> <p>有什么建议吗?提前感谢:)</p> </div>


<div class="post-text" itemprop="text"> <p>I want to convert the timestamp to <code>DayOfyearTHour:Minute.000Z</code> in golang. As i am new to golang, can someone help me please</p> <pre><code> package main import ( "fmt" "time" ) func main() { layout := "2006-01-02T15:04:05.000Z" str :="2019-05-10 19:02:27.917 +0000 UTC" t, err := time.Parse(layout, str) if err != nil { fmt.Println(err) } fmt.Println(t) } </code></pre> <p>The below is the error </p> <pre><code>parsing time "2019-05-10 19:02:27.917 +0000 UTC" as "2006-01-02T15:04:05.000Z": cannot parse " 19:02:27.917 +0000 UTC" as "T" 0001-01-01 00:00:00 +0000 UTC </code></pre> </div>

Golang io / ioutil NopCloser

<div class="post-text" itemprop="text"> <p>Does anyone have a good or any explanation of Golang's <a href="https://golang.org/pkg/io/ioutil/#NopCloser" rel="noreferrer"><code>NopCloser</code></a> function? <br> I looked around but failed to find anything besides Golang's main doc's explanation of:</p> <blockquote> <p>NopCloser returns a ReadCloser with a no-op Close method wrapping the provided Reader r.</p> </blockquote> <p>Any pointers or explanation would be appreciated. Thanks.</p> </div>


<div class="post-text" itemprop="text"> <p>ok so yes im new to golang, but not to coding, I'm a bit confused with the way functions are working with golang, in this 2 weeks I have 9 times out or 10 I had an issue it was related to funtions... I'm no lazy I have search all over for examples to inspire me, but they are all under one main() funtion. I'm trying to have a http.get in one funtion and many other functions call this funtion everytime we need to use http.get so we dont repeat code over and over.. example:(this is not the actual code)</p> <pre><code>func myfunction(site) []byte { resp, err := client.Get(site) // client is because Im tunneling thing on a proxy TOR and had to create some helpers.. but this is working ok. return resp } func magic(staff) string { // do things and create websiteurl with staff and onther contants site := myfunction(website) contents, err := html.Parse(site.Body) //.... //.... return result } main() { //... stuff happens :) } </code></pre> <p>well the error is for example because I keep changing things around and getting different errors. or not at all.. but then no result..</p> <p>cannot use <code>resp.Body</code> (type io.ReadCloser) as type <code>[]byte</code> in return argument ./gobot.go:71: cannot use site (type []byte) as type io.Reader in argument to html.Parse:</p> <p>when I do not get an error that is how I did it the first time the Site.Body will do nothing when parsing... I put a couple of debug prints to STDOUT and I had results like two sequence of numbers.</p> <p>so basically how do I return a "result" of my query from one function to the original so it can then be parse and used? I hate to repeat code so trying to keep the repetitive code in one function and have it get it call when needed it.</p> <p>thanks</p> </div>


<div class="post-text" itemprop="text"> <p>I'm trying to write a simple sockets based go server. I'm just wondering how does the connection.Read below knows when to stop reading. (Note: this is not my code, I copied it from <a href="https://stackoverflow.com/questions/2886719/unix-sockets-in-go">Unix Sockets in Go</a> as example)</p> <pre><code>package main import ( "log" "net" ) func echoServer(c net.Conn) { for { buf := make([]byte, 512) nr, err := c.Read(buf) if err != nil { return } data := buf[0:nr] println("Server got:", string(data)) _, err = c.Write(data) if err != nil { log.Fatal("Write: ", err) } } } func main() { l, err := net.Listen("unix", "/tmp/echo.sock") if err != nil { log.Fatal("listen error:", err) } for { fd, err := l.Accept() if err != nil { log.Fatal("accept error:", err) } go echoServer(fd) } } </code></pre> <p>Is it the EOF character or there's something else? It would be really helpful if someone can point me to a link official go docs. Thanks.</p> </div>


<div class="post-text" itemprop="text"> <p>Trying to compile the following (github.com/alexedwards/scs) from source but I keep getting an error and don't understand what Im doing wrong </p> <p>The error is as follows...</p> <pre><code>go/src/github.com/alexedwards/scs/session.go:69:11: undefined: http.SameSite </code></pre> <p>I have edited mine like this</p> <pre><code>Cookie: SessionCookie{ Name: "session", Domain: "my domain name", HttpOnly: true, Path: "/", Persist: true, Secure: false, SameSite: http.SameSiteLaxMode, </code></pre> </div>

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JDK1.8 API 中文谷歌翻译版 java帮助文档 JDK API java 帮助文档 谷歌翻译 JDK1.8 API 中文 谷歌翻译版 java帮助文档 Java最新帮助文档 本帮助文档是使用谷


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这是一个门针对零基础学员学习微信小程序开发的视频教学课程。课程采用腾讯官方文档作为教程的唯一技术资料来源。杜绝网络上质量良莠不齐的资料给学员学习带来的障碍。 视频课程按照开发工具的下载、安装、使用、程序结构、视图层、逻辑层、微信小程序等几个部分组织课程,详细讲解整个小程序的开发过程


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2019 Python开发者日-培训



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本课程从初学者角度出发,提供了C#从入门到成为程序开发高手所需要掌握的各方面知识和技术。 【课程特点】 1 由浅入深,编排合理; 2 视频讲解,精彩详尽; 3 丰富实例,轻松易学; 4 每章总结配有难点解析文档。 15大章节,228课时,1756分钟与你一同进步!


编程实现学生基本信息管理程序。学生基本信息包括:学号、姓名、性别、年龄、班级、学院、专业等。具体实现的管理功能如下: (1) 输入并显示多个学生的基本信息; (2) 可根据需要实现学生信息的添加; (

android 漂亮的UI界面 完整的界面设计

声明:这也是我学习时在网上下载的,鉴于分享精神,并且觉得很不错才上传上来的。。。。。 android 漂亮的UI界面 完整的界面设计 这是一个完整的UI设计,但是没写动作,这是一个公司程序员的公司任务


Anacond的介绍 Anaconda指的是一个开源的Python发行版本,其包含了conda、Python等180多个科学包及其依赖项。 因为包含了大量的科学包,Anaconda 的下载文件比较大(约 531 MB),如果只需要某些包,或者需要节省带宽或存储空间,也可以使用Miniconda这个较小的发行版(仅包含conda和 Python)。 Conda是一个开源的包、环境管理器,可以用于...


DirectX修复工具(DirectX Repair)是一款系统级工具软件,简便易用。本程序为绿色版,无需安装,可直接运行。 本程序的主要功能是检测当前系统的DirectX状态,如果发现异常则进行修复

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