Author Archives: Robins

Android Studio sync build.gradle appears: Failed to resolve: com.android.support:appcompat problem

After initializing a project using Android Studio, you need to sync the app/build.gradle file, but it will report an error such as:

Failed to resolve: com.android.support:appcompat-v7:26.0.0

What is the reason for this?
If your Android SDK is greater than 26.0.0, you will need to add the following statements in build.Gradle in the root directory of your project:

...

allprojects {
    repositories {
        ...
        maven {
            url "https://maven.google.com"
        }
    }
}

...

Refer to the link
In addition, if it still doesn’t work, let’s see if the SDK version is correct. In app/build.gradle, there is a column of data that is buildToolsVersion, and we should write its SDK version

[mysql] “Failed to start MySQL Server” error resolution

The attention! Attention! Attention! The following operation, please read and then decide on your own whether to adopt this recommendation!
.
.
, then the text begins
drummed up mysql again recently, met a haven’t seen before.
the problem are as follows:

baidu for a long time, found that the articles are the same, the solutions are almost the same, but in here I have no use.
so looked over the wall of the outside world, finally found a useful solution.


mysql at initialization time, directory will detect whether there is if not, mysql creates it if there is, and the data are there in this directory, mysql complains, initialization and termination of if none of the above problems, it may be that the folder permissions problems solution (here in my operation path, for example, specific please refer to our own path) :


2, through the above we can see :datadir path and socket path. . 

chmod -R 777 /var/lib/mysql

3, next delete /var/lib/mysql folder contents :

rm -rf /var/lib/mysql/*

4, restart service :

service mysqld restart

at this point, if you look at the status, you can see mysql is up :

Recipe for target’Project 1.exe’ failed Cause analysis and solution

Background: The end of the B tree implementation, multi – file programming.

The following error occurred on CodeBlock

ld returned 1 exit status this error has been encountered before, because the previously run program was not closed, it can be compiled after closing.
But I don’t have a running application window here, so that’s not the case.
Search engine search, tried a lot of methods, no results.

The compiler has too little information to debug. Guess it’s CodeBlock. Try dev instead.
The following error occurred on Dev

# Project: Project1
# Makefile created by Dev-C++ 5.11

CPP      = g++.exe -D__DEBUG__
CC       = gcc.exe -D__DEBUG__
WINDRES  = windres.exe
OBJ      = B_tree.o main.o
LINKOBJ  = B_tree.o main.o
LIBS     = -L"D:/Program Files (x86)/Dev-Cpp/MinGW32/lib" -L"D:/Program Files (x86)/Dev-Cpp/MinGW32/mingw32/lib" -static-libstdc++ -static-libgcc -g3
INCS     = -I"D:/Program Files (x86)/Dev-Cpp/MinGW32/include" -I"D:/Program Files (x86)/Dev-Cpp/MinGW32/mingw32/include" -I"D:/Program Files (x86)/Dev-Cpp/MinGW32/lib/gcc/mingw32/4.8.1/include"
CXXINCS  = -I"D:/Program Files (x86)/Dev-Cpp/MinGW32/include" -I"D:/Program Files (x86)/Dev-Cpp/MinGW32/mingw32/include" -I"D:/Program Files (x86)/Dev-Cpp/MinGW32/lib/gcc/mingw32/4.8.1/include" -I"D:/Program Files (x86)/Dev-Cpp/MinGW32/lib/gcc/mingw32/4.8.1/include/c++"
BIN      = Project1.exe
CXXFLAGS = $(CXXINCS) -g3
CFLAGS   = $(INCS) -g3
RM       = rm.exe -f

.PHONY: all all-before all-after clean clean-custom

all: all-before $(BIN) all-after

clean: clean-custom
	${RM} $(OBJ) $(BIN)

$(BIN): $(OBJ)
	$(CPP) $(LINKOBJ) -o $(BIN) $(LIBS)

B_tree.o: B_tree.cpp
	$(CPP) -c B_tree.cpp -o B_tree.o $(CXXFLAGS)

main.o: main.cpp
	$(CPP) -c main.cpp -o main.o $(CXXFLAGS)

Line 25 is marked red and prompted by the compiler
25 C:\Users\ASUS\Desktop\ makefile.win recipe for target 'item 1. Exe' failed
>
>
>
2. Task manager ended collect2.exe (I didn’t see it in task manager)
3. Other Settings on attributes (some tried but failed, some didn’t dare to try)
Then saw an article: IT in the house of a blog post, link is as follows: http://www.it1352.com/369267.html

similar, is also 25 line error, but he’s a good look at the compiler information (see the full) than me, he said that the compiler meaning is as follows:
he repeats the main function of definition,
the first time and then the main definition in which files which line
and then two rows behind the information mentioned above.
His solution is to delete the duplicate main
what???

python3 install pillow error

preface
We recently used the Pillow library to train the captcha model, but it won’t install either live or dead
The environment
Docker is installed in python3
Trying to install
pip install pillow
easy_install Pillow
pipenv install pillow
As a result, they just can’t fit
The error is as follows:

Collecting pillow
  Using cached https://files.pythonhosted.org/packages/5b/bb/cdc8086db1f15d0664dd22a62c69613cdc00f1dd430b5b19df1bea83f2a3/Pillow-6.2.1.tar.gz
Building wheels for collected packages: pillow
  Building wheel for pillow (setup.py) ... error
  ERROR: Complete output from command /usr/local/bin/python -u -c 'import setuptools, tokenize;__file__='"'"'/tmp/pip-install-1vq2qpq_/pillow/setup.py'"'"';f=getattr(tokenize, '"'"'open'"'"', open)(__file__);code=f.read().replace('"'"'\r\n'"'"', '"'"'\n'"'"');f.close();exec(compile(code, __file__, '"'"'exec'"'"'))' bdist_wheel -d /tmp/pip-wheel-heq42z9x --python-tag cp37:
  ERROR: running bdist_wheel
  running build
  running build_py
  creating build
  creating build/lib.linux-x86_64-3.7
  creating build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/PngImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/PaletteFile.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/WalImageFile.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/ImagePath.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/MspImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/GifImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/SpiderImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/FliImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/CurImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/MpoImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/McIdasImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/PsdImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/EpsImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/IptcImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/XbmImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/DcxImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/ExifTags.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/FontFile.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/TiffTags.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/MpegImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/GimpPaletteFile.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/PyAccess.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/ImageFile.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/ContainerIO.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/ImageColor.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/BmpImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/IcoImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/Image.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/JpegPresets.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/ImageOps.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/Hdf5StubImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/PcdImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/ImageStat.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/ImageShow.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/PdfImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/XpmImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/ImagePalette.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/MicImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/_util.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/ImageMorph.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/FtexImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/GbrImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/ImageDraw.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/BufrStubImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/PSDraw.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/ImageDraw2.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/TarIO.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/ImtImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/FitsStubImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/_binary.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/TgaImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/ImageQt.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/PpmImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/PcfFontFile.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/ImageTk.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/ImImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/features.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/JpegImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/ImageCms.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/ImageGrab.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/SunImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/WebPImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/ImageFilter.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/FpxImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/ImageTransform.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/GdImageFile.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/__init__.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/ImageMath.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/_version.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/ImageSequence.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/__main__.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/PalmImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/PcxImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/WmfImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/DdsImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/IcnsImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/SgiImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/BlpImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/Jpeg2KImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/ImageEnhance.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/ImageFont.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/PixarImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/TiffImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/ImageWin.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/ImageMode.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/ImageChops.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/PdfParser.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/GribStubImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/GimpGradientFile.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/_tkinter_finder.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/XVThumbImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
  copying src/PIL/BdfFontFile.py -> build/lib.linux-x86_64-3.7/PIL
  running egg_info
  writing src/Pillow.egg-info/PKG-INFO
  writing dependency_links to src/Pillow.egg-info/dependency_links.txt
  writing top-level names to src/Pillow.egg-info/top_level.txt
  reading manifest file 'src/Pillow.egg-info/SOURCES.txt'
  reading manifest template 'MANIFEST.in'
  warning: no files found matching '*.c'
  warning: no files found matching '*.h'
  warning: no files found matching '*.sh'
  warning: no previously-included files found matching '.appveyor.yml'
  warning: no previously-included files found matching '.coveragerc'
  warning: no previously-included files found matching '.codecov.yml'
  warning: no previously-included files found matching '.editorconfig'
  warning: no previously-included files found matching '.readthedocs.yml'
  warning: no previously-included files found matching 'azure-pipelines.yml'
  warning: no previously-included files matching '.git*' found anywhere in distribution
  warning: no previously-included files matching '*.pyc' found anywhere in distribution
  warning: no previously-included files matching '*.so' found anywhere in distribution
  no previously-included directories found matching '.azure-pipelines'
  no previously-included directories found matching '.travis'
  writing manifest file 'src/Pillow.egg-info/SOURCES.txt'
  running build_ext
  
  
  The headers or library files could not be found for jpeg,
  a required dependency when compiling Pillow from source.
  
  Please see the install instructions at:
     https://pillow.readthedocs.io/en/latest/installation.html
  
  Traceback (most recent call last):
    File "/tmp/pip-install-1vq2qpq_/pillow/setup.py", line 888, in <module>
      zip_safe=not (debug_build() or PLATFORM_MINGW),
    File "/usr/local/lib/python3.7/site-packages/setuptools/__init__.py", line 145, in setup
      return distutils.core.setup(**attrs)
    File "/usr/local/lib/python3.7/distutils/core.py", line 148, in setup
      dist.run_commands()
    File "/usr/local/lib/python3.7/distutils/dist.py", line 966, in run_commands
      self.run_command(cmd)
    File "/usr/local/lib/python3.7/distutils/dist.py", line 985, in run_command
      cmd_obj.run()
    File "/usr/local/lib/python3.7/site-packages/wheel/bdist_wheel.py", line 192, in run
      self.run_command('build')
    File "/usr/local/lib/python3.7/distutils/cmd.py", line 313, in run_command
      self.distribution.run_command(command)
    File "/usr/local/lib/python3.7/distutils/dist.py", line 985, in run_command
      cmd_obj.run()
    File "/usr/local/lib/python3.7/distutils/command/build.py", line 135, in run
      self.run_command(cmd_name)
    File "/usr/local/lib/python3.7/distutils/cmd.py", line 313, in run_command
      self.distribution.run_command(command)
    File "/usr/local/lib/python3.7/distutils/dist.py", line 985, in run_command
      cmd_obj.run()
    File "/usr/local/lib/python3.7/distutils/command/build_ext.py", line 340, in run
      self.build_extensions()
    File "/tmp/pip-install-1vq2qpq_/pillow/setup.py", line 687, in build_extensions
      raise RequiredDependencyException(f)
  __main__.RequiredDependencyException: jpeg
  
  During handling of the above exception, another exception occurred:
  
  Traceback (most recent call last):
    File "<string>", line 1, in <module>
    File "/tmp/pip-install-1vq2qpq_/pillow/setup.py", line 903, in <module>
      raise RequiredDependencyException(msg)
  __main__.RequiredDependencyException:
  
  The headers or library files could not be found for jpeg,
  a required dependency when compiling Pillow from source.
  
  Please see the install instructions at:
     https://pillow.readthedocs.io/en/latest/installation.html
  
  
  ----------------------------------------
  ERROR: Failed building wheel for pillow
  Running setup.py clean for pillow
Failed to build pillow
Installing collected packages: pillow
  Running setup.py install for pillow ... error
    ERROR: Complete output from command /usr/local/bin/python -u -c 'import setuptools, tokenize;__file__='"'"'/tmp/pip-install-1vq2qpq_/pillow/setup.py'"'"';f=getattr(tokenize, '"'"'open'"'"', open)(__file__);code=f.read().replace('"'"'\r\n'"'"', '"'"'\n'"'"');f.close();exec(compile(code, __file__, '"'"'exec'"'"'))' install --record /tmp/pip-record-3r__g4ou/install-record.txt --single-version-externally-managed --compile:
    ERROR: running install
    running build
    running build_py
    creating build
    creating build/lib.linux-x86_64-3.7
    creating build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/PngImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/PaletteFile.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/WalImageFile.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/ImagePath.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/MspImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/GifImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/SpiderImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/FliImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/CurImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/MpoImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/McIdasImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/PsdImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/EpsImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/IptcImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/XbmImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/DcxImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/ExifTags.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/FontFile.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/TiffTags.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/MpegImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/GimpPaletteFile.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/PyAccess.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/ImageFile.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/ContainerIO.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/ImageColor.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/BmpImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/IcoImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/Image.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/JpegPresets.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/ImageOps.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/Hdf5StubImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/PcdImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/ImageStat.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/ImageShow.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/PdfImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/XpmImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/ImagePalette.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/MicImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/_util.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/ImageMorph.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/FtexImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/GbrImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/ImageDraw.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/BufrStubImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/PSDraw.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/ImageDraw2.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/TarIO.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/ImtImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/FitsStubImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/_binary.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/TgaImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/ImageQt.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/PpmImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/PcfFontFile.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/ImageTk.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/ImImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/features.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/JpegImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/ImageCms.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/ImageGrab.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/SunImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/WebPImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/ImageFilter.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/FpxImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/ImageTransform.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/GdImageFile.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/__init__.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/ImageMath.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/_version.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/ImageSequence.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/__main__.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/PalmImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/PcxImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/WmfImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/DdsImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/IcnsImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/SgiImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/BlpImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/Jpeg2KImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/ImageEnhance.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/ImageFont.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/PixarImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/TiffImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/ImageWin.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/ImageMode.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/ImageChops.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/PdfParser.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/GribStubImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/GimpGradientFile.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/_tkinter_finder.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/XVThumbImagePlugin.py -> build/lib.linux-x86_64-3.7/PIL
    copying src/PIL/BdfFontFile.py -> build/lib.linux-x86_64-3.7/PIL
    running egg_info
    writing src/Pillow.egg-info/PKG-INFO
    writing dependency_links to src/Pillow.egg-info/dependency_links.txt
    writing top-level names to src/Pillow.egg-info/top_level.txt
    reading manifest file 'src/Pillow.egg-info/SOURCES.txt'
    reading manifest template 'MANIFEST.in'
    warning: no files found matching '*.c'
    warning: no files found matching '*.h'
    warning: no files found matching '*.sh'
    warning: no previously-included files found matching '.appveyor.yml'
    warning: no previously-included files found matching '.coveragerc'
    warning: no previously-included files found matching '.codecov.yml'
    warning: no previously-included files found matching '.editorconfig'
    warning: no previously-included files found matching '.readthedocs.yml'
    warning: no previously-included files found matching 'azure-pipelines.yml'
    warning: no previously-included files matching '.git*' found anywhere in distribution
    warning: no previously-included files matching '*.pyc' found anywhere in distribution
    warning: no previously-included files matching '*.so' found anywhere in distribution
    no previously-included directories found matching '.azure-pipelines'
    no previously-included directories found matching '.travis'
    writing manifest file 'src/Pillow.egg-info/SOURCES.txt'
    running build_ext
    
    
    The headers or library files could not be found for jpeg,
    a required dependency when compiling Pillow from source.
    
    Please see the install instructions at:
       https://pillow.readthedocs.io/en/latest/installation.html
    
    Traceback (most recent call last):
      File "/tmp/pip-install-1vq2qpq_/pillow/setup.py", line 888, in <module>
        zip_safe=not (debug_build() or PLATFORM_MINGW),
      File "/usr/local/lib/python3.7/site-packages/setuptools/__init__.py", line 145, in setup
        return distutils.core.setup(**attrs)
      File "/usr/local/lib/python3.7/distutils/core.py", line 148, in setup
        dist.run_commands()
      File "/usr/local/lib/python3.7/distutils/dist.py", line 966, in run_commands
        self.run_command(cmd)
      File "/usr/local/lib/python3.7/distutils/dist.py", line 985, in run_command
        cmd_obj.run()
      File "/usr/local/lib/python3.7/site-packages/setuptools/command/install.py", line 61, in run
        return orig.install.run(self)
      File "/usr/local/lib/python3.7/distutils/command/install.py", line 545, in run
        self.run_command('build')
      File "/usr/local/lib/python3.7/distutils/cmd.py", line 313, in run_command
        self.distribution.run_command(command)
      File "/usr/local/lib/python3.7/distutils/dist.py", line 985, in run_command
        cmd_obj.run()
      File "/usr/local/lib/python3.7/distutils/command/build.py", line 135, in run
        self.run_command(cmd_name)
      File "/usr/local/lib/python3.7/distutils/cmd.py", line 313, in run_command
        self.distribution.run_command(command)
      File "/usr/local/lib/python3.7/distutils/dist.py", line 985, in run_command
        cmd_obj.run()
      File "/usr/local/lib/python3.7/distutils/command/build_ext.py", line 340, in run
        self.build_extensions()
      File "/tmp/pip-install-1vq2qpq_/pillow/setup.py", line 687, in build_extensions
        raise RequiredDependencyException(f)
    __main__.RequiredDependencyException: jpeg
    
    During handling of the above exception, another exception occurred:
    
    Traceback (most recent call last):
      File "<string>", line 1, in <module>
      File "/tmp/pip-install-1vq2qpq_/pillow/setup.py", line 903, in <module>
        raise RequiredDependencyException(msg)
    __main__.RequiredDependencyException:
    
    The headers or library files could not be found for jpeg,
    a required dependency when compiling Pillow from source.
    
    Please see the install instructions at:
       https://pillow.readthedocs.io/en/latest/installation.html
    
    
    ----------------------------------------
ERROR: Command "/usr/local/bin/python -u -c 'import setuptools, tokenize;__file__='"'"'/tmp/pip-install-1vq2qpq_/pillow/setup.py'"'"';f=getattr(tokenize, '"'"'open'"'"', open)(__file__);code=f.read().replace('"'"'\r\n'"'"', '"'"'\n'"'"');f.close();exec(compile(code, __file__, '"'"'exec'"'"'))' install --record /tmp/pip-record-3r__g4ou/install-record.txt --single-version-externally-managed --compile" failed with error code 1 in /tmp/pip-install-1vq2qpq_/pillow/

 
To solve the…
After searching on the Internet, I finally found the answer on StackOverflow. It turned out to be the lack of dependency packets
https://stackoverflow.com/questions/44043906/the-headers-or-library-files-could-not-be-found-for-jpeg-installing-pillow-on/44044479#44044479
 
The solution
Add the following to the build Dockerfile:

FROM python:alpine
RUN apk --update add libxml2-dev libxslt-dev libffi-dev gcc musl-dev libgcc openssl-dev curl
RUN apk add jpeg-dev zlib-dev freetype-dev lcms2-dev openjpeg-dev tiff-dev tk-dev tcl-dev
RUN pip install Pillow

This will allow you to build successfully
 
You can go into the container
Install these dependencies directly, and you can install them directly in the container without having to rebuild the image

apk add jpeg-dev zlib-dev freetype-dev lcms2-dev openjpeg-dev tiff-dev tk-dev tcl-dev

supplement
Good, you can happily use, other may be the permission error, or switch under the installation source

About the reason why the Raspberry Pi raspistill command cannot find the camera

You can find the camera driver on the raspberry PI, but input raspistil-o image.jpg on the raspberry PI terminal, and output the following error:

mmal: Cannot read camera info, keeping the defaults for OV5647
mmal: mmal_vc_component_create: failed to create component 'vc.ril.camera' (1:ENOMEM)
mmal: mmal_component_create_core: could not create component 'vc.ril.camera' (1)
mmal: Failed to create camera component
mmal: main: Failed to create camera component
mmal: Camera is not detected. Please check carefully the camera module is installed correctly

The reason for this is that the camera used is a USB camera, while the Raspistill command only works with the CSI camera. For the USB camera, you can access it by calling FSWEbCAM.
enter sudo apt-get install fswebcam to install fswebcam on raspberry PI terminal. Enter sudo fswebcam image.jpg for the photo test. You can use this method by entering fswebcam-h .

Failed to extend swap file from 0 kb to xxx kb.

Yesterday the esXI server of the company encountered such a problem;
Problem description:
Here’s how it works. The ESXI server has seven virtual machines, Windows and Centos. When I was setting up Jenkins’ build yesterday, when I was executing three build tasks at once (which I will limit to a single build later), the virtual machine died, “There is no more space for virtual disk Jenkins – 00002. The VMDK. You took a be able to continue this session by freeing dish space on the relevant volume, and clicking _Retry.” Then, when I started Jenkins server, I reported an exception “Failed to extend swap File from 0 KB to 5242880 KB.” Step 3: I adjusted the memory of Jenkins virtual machine, and then I could enter the virtual machine. After the above problems, I repeatedly reduced the configuration of other virtual machines, so the memory of the other six virtual machines was reduced to 1G. When Jenkins’ server went down, the only way to log in was to reduce the memory of the other virtual machines. It turned out that Jenkins’ machine couldn’t boot up even after all the machines were running with minimal memory. “Failed to extend swap File from 0 KB to XXXX KB.” In fact, What I can’t understand is, where is the memory I freed from other machines?I really can’t understand it. I didn’t think about it all night yesterday.

So spent the gloomy Saturday of helpless pain; Under the help of a friend from Shenzhen, Old K, I sorted out the train of thought and analyzed the problem.
As a part-time operation, I feel it is difficult to conquer this problem, which makes me not confident, especially when all the virtual machines on the server are very sensitive, which makes me hesitate. Nothing, yesterday also smoked two packs of cigarettes, this body. Ah!

To get down to business, solutions:
1. Refer to the official website of VMware; (Google input “Failed to extend swap File” from 0 KB to XXX KB), you will find the official website prompt;
I’m going to change the storage path of the SWAP file; Because of the risks, it was considered an alternative;

2. After analyzing for half a day, it was positioned as “esXI has insufficient disk space”. As a result, when the virtual machine started, it reported the above problem when writing swap file to the physical machine;

Solution: I delete a virtual machine on the machine and everything returns to normal. And ensure that the physical machine has enough memory, as esXI server maintenance essential knowledge;

Episode;
Yesterday I leadership said to me: you his mother even swap is what all don’t know?I can only say that I do Android development, I really don’t know, but it doesn’t matter, attitude allows you to keep solving problems). Also, I have to reflect on myself. Why don’t you even know swap?
Dedicated to 20160305, my day of anxiety.

chrome net_error_map

https://chromium.googlesource.com/chromium/src.git/+/refs/tags/74.0.3729.78/components/domain_reliability/util.cc

net_error_map[] = {
  { net::OK, "ok" },
  { net::ERR_ABORTED, "aborted" },
  { net::ERR_TIMED_OUT, "tcp.connection.timed_out" },
  { net::ERR_CONNECTION_CLOSED, "tcp.connection.closed" },
  { net::ERR_CONNECTION_RESET, "tcp.connection.reset" },
  { net::ERR_CONNECTION_REFUSED, "tcp.connection.refused" },
  { net::ERR_CONNECTION_ABORTED, "tcp.connection.aborted" },
  { net::ERR_CONNECTION_FAILED, "tcp.connection.failed" },
  { net::ERR_NAME_NOT_RESOLVED, "dns" },
  { net::ERR_SSL_PROTOCOL_ERROR, "ssl.protocol.error" },
  { net::ERR_ADDRESS_INVALID, "tcp.connection.address_invalid" },
  { net::ERR_ADDRESS_UNREACHABLE, "tcp.connection.address_unreachable" },
  { net::ERR_CONNECTION_TIMED_OUT, "tcp.connection.timed_out" },
  { net::ERR_NAME_RESOLUTION_FAILED, "dns" },
  { net::ERR_SSL_PINNED_KEY_NOT_IN_CERT_CHAIN,
        "ssl.cert.pinned_key_not_in_cert_chain" },
  { net::ERR_CERT_COMMON_NAME_INVALID, "ssl.cert.name_invalid" },
  { net::ERR_CERT_DATE_INVALID, "ssl.cert.date_invalid" },
  { net::ERR_CERT_AUTHORITY_INVALID, "ssl.cert.authority_invalid" },
  { net::ERR_CERT_REVOKED, "ssl.cert.revoked" },
  { net::ERR_CERT_INVALID, "ssl.cert.invalid" },
  { net::ERR_EMPTY_RESPONSE, "http.response.empty" },
  { net::ERR_SPDY_PING_FAILED, "spdy.ping_failed" },
  { net::ERR_SPDY_PROTOCOL_ERROR, "spdy.protocol" },
  { net::ERR_QUIC_PROTOCOL_ERROR, "quic.protocol" },
  { net::ERR_DNS_MALFORMED_RESPONSE, "dns.protocol" },
  { net::ERR_DNS_SERVER_FAILED, "dns.server" },
  { net::ERR_DNS_TIMED_OUT, "dns.timed_out" },
  { net::ERR_INSECURE_RESPONSE, "ssl" },
  { net::ERR_CONTENT_LENGTH_MISMATCH, "http.response.content_length_mismatch" },
  { net::ERR_INCOMPLETE_CHUNKED_ENCODING,
        "http.response.incomplete_chunked_encoding" },
  { net::ERR_SSL_VERSION_OR_CIPHER_MISMATCH,
        "ssl.version_or_cipher_mismatch" },
  { net::ERR_BAD_SSL_CLIENT_AUTH_CERT, "ssl.bad_client_auth_cert" },
  { net::ERR_INVALID_CHUNKED_ENCODING,
        "http.response.invalid_chunked_encoding" },
  { net::ERR_RESPONSE_HEADERS_TRUNCATED, "http.response.headers.truncated" },
  { net::ERR_REQUEST_RANGE_NOT_SATISFIABLE,
        "http.request.range_not_satisfiable" },
  { net::ERR_INVALID_RESPONSE, "http.response.invalid" },
  { net::ERR_RESPONSE_HEADERS_MULTIPLE_CONTENT_DISPOSITION,
        "http.response.headers.multiple_content_disposition" },
  { net::ERR_RESPONSE_HEADERS_MULTIPLE_CONTENT_LENGTH,
        "http.response.headers.multiple_content_length" },
  { net::ERR_SSL_UNRECOGNIZED_NAME_ALERT, "ssl.unrecognized_name_alert" }
};

 

When jar file is running: Failed to load Main-Class manifest attribute from ……Solution

The original address is:
Jar file runtime: Failed to load main-class manifest Attribute from… The solution

Failed to load main-class manifest Attribute from… , which is caused by the unset program entry program. Open the JAR file with WinRAR, expand the meta-INF folder, and check the MANIFEst.MF file. It can be found that main-class is not set, which is the reason of the exception.

reprint please indicate this article address:
Jar file runtime: Failed to load main-class manifest Attribute from… The solution

Failed to execute ‘postMessage’ on ‘DOMWindow’: The target origin provided (‘https://xxx.cn’) does n

Failed to execute ‘postMessage’ on ‘DOMWindow’: The Target Origin Provided (‘https://xxx.cn’) Does not match The Window’s Origin (‘null’).
Using the event. The source </ code> object as a letter
specific see: https://developer.mozilla.org...

// This function is called by addEventListenner when the A page postMessage is called.
function receiveMessage(event)
{
  // Can we trust the source of the information?
  if (event.origin ! == "http://example.com:8080")
    return;

  // event.source on the source page of the current popup page.
  // event.data is "hello there!"

  // Assuming you've already verified the origin of the received message (which you should do any time), a handy way to do this is to add the enent.source
  // as the object of the reply, and use event.origin as the targetOrigin.
  event.source.postMessage("hi there yourself! the secret response " +
                           "is: rheeeeet!",
                           event.origin);
}

window.addEventListener("message", receiveMessage, false);

The answer is helpful, it’s valuable 0 it’s not helpful, it’s the wrong answer, irrelevant answer
otherWindow.postMessage(message, targetOrigin, [transfer]);
otherWindow: a reference to another window, such as the contentWindow property of the iframe, the window object that executes window.open, or the named or numerically indexed window.frames.
otherWindow cannot be the current window oh
see MDN

DHCP principle and experimental verification

I. Function overview
The main function of DHCP (Dynamic Host Configuration Protocol) is to centrally manage and assign IP addresses, so that hosts in the network environment can dynamically obtain IP address, Gateway address, DNS server address and other information, and improve the utilization rate of addresses.
DHCP protocol adopts the client/server model: When the DHCP server receives the address application information from the network host, it will send the relevant address configuration information to the network host to realize the dynamic configuration of the network host address information.
Ii. Working principle
DHCP USES UDP as the transport protocol. The host sends the request message to port 67 of DHCP server, and the DHCP server responds the reply message to port 68 of the host. The detailed interaction is as follows.
(1) DHCP Client sends DHCP Discover message by broadcasting.

    (2) all DHCP servers can receive DHCP Discover message sent by the DHCP Client, and all DHCP servers will give a response and send a DHCP Offer message to the DHCP Client. (3) The “Your(Client) IP Address” field in the DHCP Offer packet is the IP Address that DHCP Server can provide to THE DHCP Client, and DHCP Server will put its IP Address in the “Option” field so that DHCP Client can distinguish different DHCP servers. The DHCP Server will have a record of the assigned IP address after sending this message. (4) DHCP Client can only handle one DHCP Offer packet among them, and the general principle is that DHCP Client can handle the DHCP Offer packet that it receives first. (5) The DHCP Client will send a broadcast DHCP Request message, and add the IP address and the required IP address of the selected DHCP Server into the option field. (6) After the DHCP Server receives the DHCP Request message, it shall determine whether the IP address in the option field is the same as its own address. If it is not the same, DHCP Server does not do anything but clear the corresponding IP address assignment record; If the same is true, the DHCP Server will respond to the DHCP Client with a DHCP ACK packet and add the usage lease information for the IP address in the options field. (7) After the DHCP Client receives the DHCP ACK packet, it shall check whether the IP address assigned by the DHCP Server can be used. If it can be used, then the DHCP Client successfully obtains the IP address and automatically starts the renewal process by using the lease term according to the IP address; If the DHCP Client finds that the assigned IP address has been used, the DHCP Client will send the DHCP Decline message to the DHCPServer, notify the DHCPServer to disable this IP address, and then the DHCP Client will start the new address application process. (8) After the DHCP Client successfully obtains the IP address, it can Release its IP address at any time by sending THE DHCP Release message. After the DHCP Server receives the DHCP Release message, it will recover the corresponding IP address and reassigned it. 3. Experimental verification: After DHCP services are configured on servers and network devices (routers and switches), DHCP can generally be used as DHCP servers. In this experiment, routers were used to simulate the network topology, as shown in the figure below: In the diagram, routers were dhCP-server and switches were two-layer devices (switch ports connected to PC1-6 hosts were all in the default VLAN 1).

1. Before the configuration of dhcp-server is completed, PC1 is configured to DHCP to get the IP address, which is shown as follows:

The result shows “DHCP failed. APIPA is being used”, indicating that the IP address was not successfully obtained (generally a “169.254.0.0/16” segment address is displayed, indicating that the IP address was not obtained from the DHCP server).
2. Configure DHCP related information on the router:
(1) configure port IP as shown in the figure below:

(2) configure DHCP service as shown in the figure below:

3. At this point, verify the IP address acquisition above PC1:

As can be seen from the figure above, PC1 successfully obtained the CONFIGURATION information of IP address, gateway, DNS-Server, etc.

Reproduced in: https://blog.51cto.com/13401027/1977218

(EE) Failed to load module “fbdev” (module does not exist, 0)

Enter the command startx in the virtual machine:
The following error occurs.
(EE) Failure to load module “Video Electronics Standards Association” (module does not exist, 0)
(EE) failed to load module “fbdev” (module does not exist, 0)
(EE) failed to load module “evdev” (module does not exist, 0)
(EE)No driver matching evdev input
(EE) failed to load module “evdev” (module does not exist, 0)
(EE)No driver matching evdev input
(EE) failed to load module “evdev” (module does not exist, 0)
(EE) No input driver matches “evdev”Solution.
yum install xorg-x11-drivers