AAAAAAAAAH sorry! It was a really tough day and I tried to code in the worst situation ever, I was really tired that I did not even noticed how stupid and newbie was that, sorry! PLEASE just ignore my last comment... ahah Im REALLY embarrassed After a break of 2 days, I went back on my code, and after some trials I got something weird. Im trying something simple. to test what happens between each step to get out fron that situation- from an io.writer to *bytes.Buffer to []byte and viceversa.. Well, once compailed, everything works fine, expect the stout:
once I get the shell, the command /bin/sh -i gets executed If from the server I type a non existing command, *I get the sterr on the server, but I don't get the stout ... I wanna smash my keyboard . https://play.golang.org/p/RWs7Kkccz-S* *I mean, if I use these exact line on a simple command in another project, everything works fine, but in that situation it does not, its like if stout goes lost in the space: * I hope I won't hurt your brain again ahah Sorry again, I did not mean that! ahah I Il giorno giovedì 8 luglio 2021 alle 20:43:31 UTC+2 Brian Candler ha scritto: > Complete code on play.golang.org is much easier to understand. At the > moment I don't think your code will do anything useful. For example > > buf := new(bytes.Buffer) > ... > bizz := buf.Bytes() > > will always set bizz to an empty slice; since you never modify bizz, > len(bizz) will always be zero. Also, > > kk := io.Writer(z) > > creates an io.Writer variable with a particular value, but never uses that > value, because 2 lines later you replace it with a different value. I > can't say for sure without seeing the whole program, but I don't think > that's where the error is occurring; I think it's the later line ("kk = > conn"), because you don't seem to use that value. It's as if you wrote a > program like this: > > func main() { > i := 1 > i = 2 > } > > i.e. you just return and never use the value of "i". > > I think the previous advice given was good. Do the go tour, several times > if required; look at the tutorials at https://golang.org/doc/, look for > interesting articles at https://blog.golang.org/index; after you pick up > the core concepts, find some example sockets-based code, run it, modify > it. Stringing together statements, if you don't understand what each > individual statement does, is unlikely to give a useful result. > > On Thursday, 8 July 2021 at 18:54:29 UTC+1 LetGo wrote: > >> I thought that after getting the bytes, chunk the data, I need to have >> the io.writer back before send the chunked data >> So far I came up with this: >> >> ... >> cmd.Stdin = conn >> buf := new(bytes.Buffer) >> cmd.Stdout = buf >> >> bizz := buf.Bytes() >> >> var i int >> for { >> n := int(math.Min(float64(rand.Intn(len(bizz))), float64(len(bizz)))) >> d := bizz[i : i+n] >> i += n >> >> >> z := bytes.NewBuffer(d) >> >> kk := io.Writer(z) >> //this line creates the error >> >> time.Sleep(400 * time.Millisecond) >> >> kk = conn >> >> >> if i >= len(bizz) { >> break >> } >> } >> cmd.Stderr = conn >> cmd.Run() >> ..... >> >> But know I get this error: >> >> conn.go:95:21: kk declared but not used >> Il giorno mercoledì 7 luglio 2021 alle 15:49:56 UTC+2 mlevi...@gmail.com >> ha scritto: >> >>> 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 <non3...@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...@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. 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/5930a8c1-5eea-40d0-8a48-82fbdb3432a9n%40googlegroups.com.
