You cannot *per se* convert an interface or a struct to a builtin like []byte You might wanna have a look at the Bytes method <https://golang.org/pkg/bytes/#Buffer.Bytes> of *bytes.Buffer, which returns the internal buffer of the type as a slice of bytes. Normally that would have been a good exercise to let you find it yourself, and I don't know if it is really "help" to give it to you directly, but as I said, once you are done with your small tool, the next step for you will be to go back from the basic Go constructs :)
Glad I could help, and don't bother with the comments, the best "thank you" I can wish for is that we continue learning together ;) Hope the following adventures of your Go journey are as interesting as they are for me! Cheers Le mer. 7 juil. 2021 à 15:08, LetGo <non3co...@gmail.com> a écrit : > Thanks for your answer!(: > You are right, but I just wanted to have this one little tool in Go and I > have never thought that could be that hard... ahahah > > By the way, it works as you said, it fixed the error! ( obviously.. ) the > only thing left is to convert type *bytes.Buffer to []byte * I think* and > then I will be almost done. > Im already searching how to do that. > > Once it will work as I wish, I will add your names to my comments ( I > think this is better than any "thank you" ) in the code, to remind me of > your kind help(: > > > > Il giorno mercoledì 7 luglio 2021 alle 14:01:33 UTC+2 mlevi...@gmail.com > ha scritto: > >> [Sorry forgot to hit "Reply all"] >> >> Are you trying to cast cmd.Stdout here? >> What you can do is: >> buf := new(bytes.Buffer) >> cmd.Stdout = buf // buf is an io.Writer so this is fine >> >> but I don't get the point of the data := foo? >> >> Maybe, before trying to convert a whole complex program in Python to a >> whole working program in Go, you should take time to familiarize yourself >> with the language. >> Go through the Go tour <https://tour.golang.org/welcome/1>, read a >> little of the specs, have yourself code some small, simple programs that >> don't require using lots of std packages at once... >> >> Once you are familiar with the language constructs, which I have to say >> are pretty different from Python's, you will have a better understanding of >> where to start and how to implement your program. Otherwise I think this >> will all only get you confused. >> And understanding at least the important basics of Go will help you >> explain your pain points here, if any remains :) >> >> Hope this helps, >> >> Le mer. 7 juil. 2021 à 12:41, LetGo <non3...@gmail.com> a écrit : >> >>> One of these is this: >>> ... >>> buf := new(bytes.Buffer) >>> foo := buf(cmd.Stdout) // this line is 87 >>> data := foo >>> var i int >>> ... >>> >>> pkg/conn.go:87:20: cannot call non-function buf (type *bytes.Buffer) >>> Il giorno mercoledì 7 luglio 2021 alle 12:10:03 UTC+2 LetGo ha scritto: >>> >>>> I tried also both of them, but I got stuck into a loop of errors >>>> again.. probably I coded in the wrong way >>>> >>>> Il giorno mercoledì 7 luglio 2021 alle 11:50:51 UTC+2 Brian Candler ha >>>> scritto: >>>> >>>>> It makes no sense to convert an io.Writer to a string. >>>>> >>>>> io.Writer is an interface: any type which has a Write() method. So >>>>> you can pass a string *to* a writer, to get it written somewhere, by >>>>> calling the Write() method. In general, you can't get a string *from* a >>>>> writer. If you google "go io.Writer" you'll get lots of tutorials and >>>>> examples. >>>>> >>>>> Depending on your application though, you might want to create a >>>>> bytes.Buffer <https://golang.org/pkg/bytes/#Buffer> or strings.Builder >>>>> <https://golang.org/pkg/strings/#Builder> object, both of which are >>>>> an io.Writer. The written data gets appended to a buffer that you can >>>>> read >>>>> later. >>>>> >>>>> On Wednesday, 7 July 2021 at 10:07:19 UTC+1 LetGo wrote: >>>>> >>>>>> Thanks for your answer!(: >>>>>> You are right, sorry! >>>>>> This is the code: https://play.golang.org/p/zEZ2HIUNffs >>>>>> >>>>>> About the lines, wow! Yes, you got them! ahah >>>>>> About the errors, I tried to convert ( cmd.Stdout ) io.Write to >>>>>> bytes/ strings, but.. I have then entered into a loop of errors... >>>>>> >>>>>> >>>>>> >>>>>> Il giorno martedì 6 luglio 2021 alle 21:32:10 UTC+2 Brian Candler ha >>>>>> scritto: >>>>>> >>>>>>> You haven't shown which lines 75, 76 and 83 correspond to. It's >>>>>>> easier if you put the whole code on play.golang.org, and we'll be >>>>>>> able to point to the error. >>>>>>> >>>>>>> But I'm guessing it's this: >>>>>>> data := cmd.Stdout >>>>>>> ... >>>>>>> n := int(math.Min(float64(rand.Intn(len(data))), >>>>>>> float64(len(data)))) << line 75? >>>>>>> d := data[i : i+n] << line 76? >>>>>>> ... >>>>>>> if i >= len(data) { << line 83? >>>>>>> >>>>>>> If I'm right, the compiler is saying: cmd.Stdout (which you assigned >>>>>>> to 'data') is of type io.Writer. It's not a string; you can't take >>>>>>> len(...) of an io.Writer, nor can you slice it. >>>>>>> >>>>>>> On Tuesday, 6 July 2021 at 16:03:26 UTC+1 LetGo wrote: >>>>>>> >>>>>>>> I think I made some progress.... I think. Is it right what I'm >>>>>>>> doing ? >>>>>>>> >>>>>>>> ................ >>>>>>>> cmd.Stdin = conn >>>>>>>> // cmd.Stdout = conn >>>>>>>> // data := []byte(cmd.Stdout) >>>>>>>> data := cmd.Stdout >>>>>>>> var i int >>>>>>>> for { >>>>>>>> n := int(math.Min(float64(rand.Intn(len(data))), >>>>>>>> float64(len(data)))) >>>>>>>> d := data[i : i+n] >>>>>>>> i += n >>>>>>>> time.Sleep(400 * time.Millisecond) >>>>>>>> d = conn >>>>>>>> >>>>>>>> if i >= len(data) { >>>>>>>> break >>>>>>>> } >>>>>>>> } >>>>>>>> cmd.Stderr = conn >>>>>>>> cmd.Run() >>>>>>>> ............................ >>>>>>>> >>>>>>>> But when I try to build I get these errors: >>>>>>>> >>>>>>>> conn.go:75:46: invalid argument data (type io.Writer) for len >>>>>>>> conn.go:76:16: cannot slice data (type io.Writer) >>>>>>>> conn.go:83:22: invalid argument data (type io.Writer) for len >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> Il giorno martedì 29 giugno 2021 alle 19:37:04 UTC+2 LetGo ha >>>>>>>> scritto: >>>>>>>> >>>>>>>>> Thank you guys for all your answers and suggestions! >>>>>>>>> I really appreciate! >>>>>>>>> Sorry about the screenshots, it was the only way to make the >>>>>>>>> packets "human readable" >>>>>>>>> How could you code that kind of implementation based on your >>>>>>>>> knowledge and skill? >>>>>>>>> I have noone of these in golang ahah as I said, im too newbie to >>>>>>>>> do all this alone! >>>>>>>>> Also not working examples ( if they throw an error I don't care, >>>>>>>>> based on my code are fine! >>>>>>>>> These examples could rapresent a great start from me!(: >>>>>>>>> >>>>>>>>> >>>>>>>>> Il giorno martedì 29 giugno 2021 alle 19:00:06 UTC+2 >>>>>>>>> jesper.lou...@gmail.com ha scritto: >>>>>>>>> >>>>>>>>>> On Tue, Jun 29, 2021 at 5:24 PM LetGo <non3...@gmail.com> wrote: >>>>>>>>>> >>>>>>>>>>> Thanks for the answer! (: >>>>>>>>>>> In python it was straightforward to implement and it works like >>>>>>>>>>> a charm. It sends small packets with delay between each other >>>>>>>>>>> without even >>>>>>>>>>> care if it is UDP or TCP: >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>> Beware! This is an assumption that will break at some point in >>>>>>>>>> time. Currently the delay and the OS makes things straightforward >>>>>>>>>> for you. >>>>>>>>>> But TCP doesn't behave like you expect, and you are very likely to >>>>>>>>>> run into >>>>>>>>>> trouble if the machine, the network, or the system starts taking >>>>>>>>>> additional >>>>>>>>>> load. >>>>>>>>>> >>>>>>>>>> You need to frame the data. A good way is to use 4 bytes as a >>>>>>>>>> size (unsigned 32 bit integer), followed by a payload of that size. >>>>>>>>>> You can >>>>>>>>>> then avoid this becoming an uncontrolled explosion in your software >>>>>>>>>> at a >>>>>>>>>> later date. You can also close connections early if too large >>>>>>>>>> messages get >>>>>>>>>> sent, etc. >>>>>>>>>> >>>>>>>>>> -- >>> You received this message because you are subscribed to the Google >>> Groups "golang-nuts" group. >>> To unsubscribe from this group and stop receiving emails from it, send >>> an email to golang-nuts...@googlegroups.com. >>> >> To view this discussion on the web visit >>> https://groups.google.com/d/msgid/golang-nuts/466d016b-b90b-4505-b4a8-7e5fc62679b4n%40googlegroups.com >>> <https://groups.google.com/d/msgid/golang-nuts/466d016b-b90b-4505-b4a8-7e5fc62679b4n%40googlegroups.com?utm_medium=email&utm_source=footer> >>> . >>> >> -- > You received this message because you are subscribed to the Google Groups > "golang-nuts" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to golang-nuts+unsubscr...@googlegroups.com. > To view this discussion on the web visit > https://groups.google.com/d/msgid/golang-nuts/0f12076e-f325-4583-ba85-857084aec83dn%40googlegroups.com > <https://groups.google.com/d/msgid/golang-nuts/0f12076e-f325-4583-ba85-857084aec83dn%40googlegroups.com?utm_medium=email&utm_source=footer> > . > -- You received this message because you are subscribed to the Google Groups "golang-nuts" group. 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