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by jahboater
Tue Feb 21, 2017 10:49 am
Forum: Troubleshooting
Topic: Pi not starting properly.... unusable.
Replies: 7
Views: 1365

Re: Pi not starting properly.... unusable.

Assuming you are using Windows, get SDFormatter 4.0 and reformat the card (or another card) using the "Format size adjustment - on" option. Then get Win32DiskImager and use it to install a fresh image of Raspbian (not lite) downloaded from here. IMO don't mess with NOOBS, it just makes things more ...
by jahboater
Mon Feb 20, 2017 7:54 am
Forum: Troubleshooting
Topic: Parallel Programming of Raspberry Pi?
Replies: 7
Views: 3298

Re: Parallel Programming of Raspberry Pi?

I would like two programs collecting some IR sensors and Sonar sensors value separately and the values then to be sent to the main running program for analysis. I reckon there should be three program running in parallel and could anyone help me how could I achieve this? Raspbian (the official Pi op...
by jahboater
Mon Feb 20, 2017 7:17 am
Forum: Beginners
Topic: customise PI image
Replies: 13
Views: 2038

Re: customise PI image

Does normal linux has a x-window manager or X screen? So i can run the GUI App on linux. Yes of course it does. I suggest you download Raspbian Jessie with Pixel from here https://www.raspberrypi.org/downloads/raspbian/ Do not get the Lite version which doesn't have the GUI. Download it and use it ...
by jahboater
Sun Feb 19, 2017 4:35 pm
Forum: C/C++
Topic: gpp 5.2 or better, providing C++14 for Jessie ?
Replies: 26
Views: 4610

Re: gpp 5.2 or better, providing C++14 for Jessie ?

Stiller wrote:unstoppable outputs by tar xvf.
Let it finish without pressing any keys. You don't want to get a couple of hours into the build and then it fails because part of the source tree is missing!
by jahboater
Sun Feb 19, 2017 4:14 pm
Forum: C/C++
Topic: gpp 5.2 or better, providing C++14 for Jessie ?
Replies: 26
Views: 4610

Re: gpp 5.2 or better, providing C++14 for Jessie ?

Stiller wrote:alright, after downloading anew now it's very busy, unstoppable outputs by tar xvf.

about the SD: as stated it's 32 GB, no big files on it, but no idea how much free space though. How would I know that?
Should be plenty of space, try "df -h" too see how much there is.
by jahboater
Sun Feb 19, 2017 2:38 pm
Forum: C/C++
Topic: gpp 5.2 or better, providing C++14 for Jessie ?
Replies: 26
Views: 4610

Re: gpp 5.2 or better, providing C++14 for Jessie ?

but what means "contrib/download_prerequisites" ? Is that a command? or is also for a cd ? Its a command provided by GCC to download the source of the things like GMP and MPFR that the compiler uses. They get placed in the build tree and are automatically included in the build. Very useful as it en...
by jahboater
Sun Feb 19, 2017 2:24 pm
Forum: C/C++
Topic: gpp 5.2 or better, providing C++14 for Jessie ?
Replies: 26
Views: 4610

Re: gpp 5.2 or better, providing C++14 for Jessie ?

that was in the tar command Never ever seen that before. Are you certain the download completed OK, you didn't break into it by any chance? Have you got enough disk space? Tar is a very reliable program, people have been using it for over 40 years. You don't have a fake, or faulty SD card have you?...
by jahboater
Sun Feb 19, 2017 2:11 pm
Forum: C/C++
Topic: gpp 5.2 or better, providing C++14 for Jessie ?
Replies: 26
Views: 4610

Re: gpp 5.2 or better, providing C++14 for Jessie ?

I started downoload from /home/pi/ was that correct? The gcc-6.3.0.tar.bz2 file is located there anyway. You can download to anywhere you like that has enough space. Then expand the tar file and it will create a directory called "gcc-6.3.0" which has a huge tree of files in it. cd into that, and st...
by jahboater
Sun Feb 19, 2017 2:04 pm
Forum: C/C++
Topic: gpp 5.2 or better, providing C++14 for Jessie ?
Replies: 26
Views: 4610

Re: gpp 5.2 or better, providing C++14 for Jessie ?

ok, download seems to be ok but then it seems to do nothing any more: The tar xf may take a few minutes as there are quite a lot of files (over 100,000 of them) and the SD card is slow. Use tar xvf if you want it to print out stuff as its going on. I tend to run the commands one by one, not all as ...
by jahboater
Sun Feb 19, 2017 1:56 pm
Forum: Advanced users
Topic: speed profit by shutdown video output
Replies: 3
Views: 624

Re: speed profit by shutdown video output

You turn it on and off with a command called tvservice.
by jahboater
Sun Feb 19, 2017 12:59 pm
Forum: C/C++
Topic: gpp 5.2 or better, providing C++14 for Jessie ?
Replies: 26
Views: 4610

Re: gpp 5.2 or better, providing C++14 for Jessie ?

trying to download the tar file, there is the error: get ftp://ftp.fu-berlin.de/unix/languages/gcc/releases/gcc-6.3.0/gcc-6.3.0.tar.bz2 get not found what kind of command command is "get" and how to install it ? perhaps wget instead? Oops sorry, it should be wget of course. My cut and paste missed!...
by jahboater
Sun Feb 19, 2017 12:28 pm
Forum: C/C++
Topic: Maximizing SIMD performance
Replies: 8
Views: 5309

Re: Maximizing SIMD performance

The NEON instruction set is better designed than SSE for two reasons - it was created several years after SSE came on the scene and it was designed as a coprocessor with plenty of "instruction space". NEON has every permutation of instruction for every data type. SSE didn't have the room in the ins...
by jahboater
Sun Feb 19, 2017 9:01 am
Forum: C/C++
Topic: gpp 5.2 or better, providing C++14 for Jessie ?
Replies: 26
Views: 4610

Re: gpp 5.2 or better, providing C++14 for Jessie ?

he thank you very much for your advice! I actually have a Pi 2, not a Pi3, and my SD card' is of 32GB, but from NOOBS (I mention that because of the swap file). So will your instruction work identically also for the my Pi 2 hardware, or has something to be changed for it? If its a new Pi2 (v1.2) th...
by jahboater
Sun Feb 19, 2017 8:44 am
Forum: C/C++
Topic: Maximizing SIMD performance
Replies: 8
Views: 5309

Re: Maximizing SIMD performance

My point in posting the article is to share the idea that SIMD is not 'scary' and for those who use the crutch of the C compiler "-O3" option and assume they're code is being vectorized, they might be surprised when it isn't able to do it. Well you need more than -O3. -ftree-vectorize at the very l...
by jahboater
Sat Feb 18, 2017 9:39 pm
Forum: C/C++
Topic: gpp 5.2 or better, providing C++14 for Jessie ?
Replies: 26
Views: 4610

Re: gpp 5.2 or better, providing C++14 for Jessie ?

hello, what must I do to install gpp 5.2 or better feat. C++14 for Jessie ? I just purchased a C++ guide book which introduces especially to C++14 features and so requires 5.2 or better as stated in the preamble. Will this 5.x version then also work trouble-free and out of the box with the current ...
by jahboater
Fri Feb 17, 2017 10:07 pm
Forum: Raspberry Pi OS
Topic: Help for raspian booting problem
Replies: 14
Views: 2499

Re: Help for raspian booting problem

DougieLawson wrote:You made a wrong choice. You should always take a backup just before you make a non-reversible change.
You mean apart from trying to install upstart :)
by jahboater
Fri Feb 17, 2017 5:19 pm
Forum: Troubleshooting
Topic: grep [a-zA-Z] only finds "r"
Replies: 5
Views: 908

Re: grep [a-zA-Z] only finds "r"

You might need some extra brackets for that?
by jahboater
Fri Feb 17, 2017 5:10 pm
Forum: Raspberry Pi OS
Topic: Help for raspian booting problem
Replies: 14
Views: 2499

Re: Help for raspian booting problem

1) It's not what I'm used to. (I've been using Linux & BSD since 1999, & haven't needed it.) 2) It has worked it's way into many programs, making some of them incompatible with other init systems. 3) It's not the unix way. 4) It stores it's data as binary, (so I'm told, which makes problem solving ...
by jahboater
Fri Feb 17, 2017 4:54 pm
Forum: Beginners
Topic: About External USB Drives
Replies: 7
Views: 1502

Re: About External USB Drives

BrianOBrien wrote: Now that it's mounted can't i repartition it and format it?
If so, how?
You should unmount it first with umount (see man umount for details).
by jahboater
Fri Feb 17, 2017 4:46 pm
Forum: Troubleshooting
Topic: grep [a-zA-Z] only finds "r"
Replies: 5
Views: 908

Re: grep [a-zA-Z] only finds "r"

Wondering if anyone else has encountered this issue: grep [a-zA-Z] filename This sequence was working, but suddenly stopped (pi 3B). Now it only finds the "r" if the file contains the entire alphabet. All other grep usage seems to work fine and this usage still workes just fine on another ripi. Tri...
by jahboater
Fri Feb 17, 2017 3:34 pm
Forum: Advanced users
Topic: How far have you overclocked?
Replies: 4
Views: 7288

Re: How far have you overclocked?

Trouble is most people have moved on to the Pi2 or probably the Pi3. The Pi3 is quad core armv8 (compared to single core armv6 on the B+) at 1.2GHz with 1GB of ram.

If speed is what you are after, the Pi3 is many many times faster than the B+ (ten times or more) and its the same purchase price!
by jahboater
Fri Feb 17, 2017 3:18 pm
Forum: General discussion
Topic: Read USB MBR Data and modify
Replies: 6
Views: 1313

Re: Read USB MBR Data and modify

Thats cool! But why the seek(512)? surely it starts at offset zero. After changing the MBR a seek(0) would be needed in order to rewind the file and write out the new MBR starting at zero. Or have I missed something?
by jahboater
Fri Feb 17, 2017 3:09 pm
Forum: General discussion
Topic: Read USB MBR Data and modify
Replies: 6
Views: 1313

Re: Read USB MBR Data and modify

However, I face problems doing the same on raspberry Pi. I do CreateFile based on drive letter. (\\.\<DriveLetter> ). But CreateFile with drive letter on Raspberry Pi fails. CreateFile is a Windows API function, and "drive letters" are a Windows thing. The Raspberry Pi runs a different operating sy...
by jahboater
Fri Feb 17, 2017 2:57 pm
Forum: Beginners
Topic: customise PI image
Replies: 13
Views: 2038

Re: customise PI image

How can i customise linux kernel as per I can start my GUI on start up. I can not use raspbian. I want to customise linux as. if I will give power to raspberry pi 3, it will directly start my GUI application. I don't understand why you need to "customize" the linux kernel for this, and I don't unde...
by jahboater
Fri Feb 17, 2017 11:55 am
Forum: General discussion
Topic: Multiple concurrent uses
Replies: 3
Views: 807

Re: Multiple concurrent uses

The OS (Raspbian Linux) for the Pi is fully multi-user multi-tasking, so it can and normally does run many things concurrently. The Pi2 and Pi3 are quad-core too, so its reasonably fast. I don't know what these apps you mention are. If they are for the PC they will be for Intel x86 processors. The P...

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