Develop Reference

Failed to install pykaldi on ubuntu 18.04

I followed the instructions and ran the following to commands to install pykaldi:
git clone https://github.com/pykaldi/pykaldi.git
cd pykaldi
sudo apt-get install autoconf automake cmake curl g++ git graphviz libatlas3-base libtool make pkg-config subversion unzip wget zlib1g-dev
sudo apt install intel-mkl-64bit-2020.4-912
python3.7 -m pip install --upgrade pip setuptools
python3.7 -m pip install numpy pyparsing ninja==1.10.0
cd tools
sudo torify ./check_dependencies.sh /usr/bin/python3.7
sudo torify ./install_protobuf.sh /usr/bin/python3.7
sudo torify ./install_clif.sh /usr/bin/python3.7
sudo torify ./install_kaldi.sh
cd ..
python3.7 -m pip install setuptools
sudo apt-get install ninja-build
sudo python3.7 setup.py install
when it comes to the last line, I get the following error:
running install
running bdist_egg
running egg_info
writing pykaldi.egg-info/PKG-INFO
writing dependency_links to pykaldi.egg-info/dependency_links.txt
writing requirements to pykaldi.egg-info/requires.txt
writing top-level names to pykaldi.egg-info/top_level.txt
reading manifest file 'pykaldi.egg-info/SOURCES.txt'
adding license file 'LICENSE'
writing manifest file 'pykaldi.egg-info/SOURCES.txt'
installing library code to build/bdist.linux-x86_64/egg
running install_lib
running build_py
running build_ext
Using PYCLIF: /usr/local/bin/pyclif
Using CLIF_MATCHER: /usr/clang/bin/clif-matcher
-- Configuring done
-- Generating done
-- Build files have been written to: /home/soroushh/KhodnevisProjects/wav2vec-u/pykaldi/build
[6/505] Building CXX object kaldi/matrix/CMakeFiles/_matrix_ext.dir/matrix-ext.cc.o
FAILED: kaldi/matrix/CMakeFiles/_matrix_ext.dir/matrix-ext.cc.o
/usr/bin/c++ -D_matrix_ext_EXPORTS -I../kaldi/lib -I../kaldi -Ikaldi -I../tools/kaldi/src -I/usr/include/python2.7 -I/home/soroushh/.local/lib/python3.7/site-packages/numpy/core/include -std=c++11 -I.. -isystem /home/soroushh/KhodnevisProjects/wav2vec-u/pykaldi/tools/kaldi/tools/openfst-1.6.7/include -O1 -Wall -Wno-sign-compare -Wno-unused-local-typedefs -Wno-deprecated-declarations -Winit-self -DKALDI_DOUBLEPRECISION=0 -DHAVE_EXECINFO_H=1 -DHAVE_CXXABI_H -DHAVE_MKL -I/opt/intel/mkl/include -m64 -msse -msse2 -pthread -g -fPIC -Wno-maybe-uninitialized -fPIC -MD -MT kaldi/matrix/CMakeFiles/_matrix_ext.dir/matrix-ext.cc.o -MF kaldi/matrix/CMakeFiles/_matrix_ext.dir/matrix-ext.cc.o.d -o kaldi/matrix/CMakeFiles/_matrix_ext.dir/matrix-ext.cc.o -c ../kaldi/matrix/matrix-ext.cc
In file included from /home/soroushh/.local/lib/python3.7/site-packages/numpy/core/include/numpy/ndarraytypes.h:4:0,
from /home/soroushh/.local/lib/python3.7/site-packages/numpy/core/include/numpy/ndarrayobject.h:12,
from /home/soroushh/.local/lib/python3.7/site-packages/numpy/core/include/numpy/arrayobject.h:4,
from ../kaldi/matrix/matrix-ext.cc:8:
/home/soroushh/.local/lib/python3.7/site-packages/numpy/core/include/numpy/npy_common.h:386:9: error: ‘Py_hash_t’ does not name a type
typedef Py_hash_t npy_hash_t;
^~~~~~~~~
In file included from /home/soroushh/.local/lib/python3.7/site-packages/numpy/core/include/numpy/ndarrayobject.h:12:0,
from /home/soroushh/.local/lib/python3.7/site-packages/numpy/core/include/numpy/arrayobject.h:4,
from ../kaldi/matrix/matrix-ext.cc:8:
/home/soroushh/.local/lib/python3.7/site-packages/numpy/core/include/numpy/ndarraytypes.h:655:9: error: ‘npy_hash_t’ does not name a type; did you mean ‘npy_half’?
npy_hash_t hash;
^~~~~~~~~~
npy_half
[11/505] Building CXX object kaldi/chain/CMakeFiles/_chain_generic_numerator.dir/chain-generic-numerator-clifwrap.cc.o
ninja: build stopped: subcommand failed.
Command '['ninja', '-j', '6']' returned non-zero exit status 1.
I also tried different versions of PyKaldi, i.e. 1.8.0 and 1.10.0. But it shows the same error.
Edit 1: when I execute /usr/bin/ninja -j 6 I get the following error: ninja: error: loading 'build.ninja': No such file or directory

python buildpack - fatal error: sasl/sasl.h: No such file or directory

I get the following error installing sasl in my Bluemix app:
Installing collected packages: sasl, thrift-sasl
Running setup.py install for sasl: started
Running setup.py install for sasl: finished with status 'error'
Command "/app/.heroku/python/bin/python -u -c "import setuptools, tokenize;__file__='/tmp/pip-build-9mi8225r/sasl/setup.py';exec(compile(getattr(tokenize, 'open', open)(__file__).read().replace('\r\n', '\n'), __file__, 'exec'))" install --record /tmp/pip-3l4o04ga-record/install-record.txt --single-version-externally-managed --compile" failed with error code 1 in /tmp/pip-build-9mi8225r/sasl/
running install
running build_py
creating build
creating build/lib.linux-x86_64-3.5
creating build/lib.linux-x86_64-3.5/sasl
copying sasl/__init__.py -> build/lib.linux-x86_64-3.5/sasl
running egg_info
writing dependency_links to sasl.egg-info/dependency_links.txt
writing top-level names to sasl.egg-info/top_level.txt
warning: manifest_maker: standard file '-c' not found
reading manifest file 'sasl.egg-info/SOURCES.txt'
writing manifest file 'sasl.egg-info/SOURCES.txt'
copying sasl/saslwrapper.cpp -> build/lib.linux-x86_64-3.5/sasl
copying sasl/saslwrapper.pyx -> build/lib.linux-x86_64-3.5/sasl
building 'sasl.saslwrapper' extension
creating build/temp.linux-x86_64-3.5
creating build/temp.linux-x86_64-3.5/sasl
gcc -pthread -Wno-unused-result -Wsign-compare -Wunreachable-code -DNDEBUG -g -fwrapv -O3 -Wall -Wstrict-prototypes -fPIC -Isasl -I/app/.heroku/python/include/python3.5m -c sasl/saslwrapper.cpp -o build/temp.linux-x86_64-3.5/sasl/saslwrapper.o
sasl/saslwrapper.h:22:23: fatal error: sasl/sasl.h: No such file or directory
#include <sasl/sasl.h>
^
compilation terminated.
I'm using the buildpack: python 1.5.5
My runtime.txt contains: python-3.5.0
How can I install the necessary headers in the buildpack?
Update:
It looks as though the latest cloud foundry stack has the sasl library: https://github.com/cloudfoundry/cflinuxfs2/blob/1.119.0/cflinuxfs2/build/install-packages.sh#L98.
How can I use this stack on Bluemix?

Maybe you should install some system libraries before you can install sasl refer to https://pypi.python.org/pypi/sasl/0.1.3
This library contains C++ code, and will require some additional
system libraries installed.
Debian/Ubuntu
apt-get install python-dev libsasl2-dev gcc
CentOS/RHEL
yum install gcc-c++ python-devel.x86_64
cyrus-sasl-devel.x86_64

The solution for me was to use pure-sasl and install imypla and thrift_sasl from application code rather than my requirements.txt:
try:
import impyla
except ImportError:
print("Installing missing impyla")
import pip
pip.main(['install', '--no-deps', 'impyla'])
try:
import thrift_sasl
except ImportError:
print("Installing missing thrift_sasl")
import pip
# need a patched version of thrift_sasl. see https://github.com/cloudera/impyla/issues/238
pip.main(['install', '--no-deps', 'git+https://github.com/snowch/thrift_sasl'])
I added this code to a view in my flask application: https://github.com/snowch/movie-recommender-demo/blob/master/web_app/app/main/views.py

I was having similar error -
In file included from sasl/saslwrapper.cpp:254:0:
sasl/saslwrapper.h:22:23: fatal error: sasl/sasl.h: No such file or directory
#include <sasl/sasl.h>
^
compilation terminated.
error: command 'gcc' failed with exit status 1
Try this thread it was helpful for me
I can't install python-ldap

Error installing python package in apartment with wifi

In Windows 10, I installed the linux subsystem.
In cmd, I run bash.
In bash,
I found that my current Python is 2.7.6.
I want to install the regex python library. But there is error in the following, and does someone know the solution?.
Thanks.
$ sudo python get-pip.py
sudo: unable to resolve host TINGL-ND1
The directory '/home/t/.cache/pip/http' or its parent directory is not owned by the current user and the cache has been\
disabled. Please check the permissions and owner of that directory. If executing pip with sudo, you may want sudo's -H\
flag.
The directory '/home/t/.cache/pip' or its parent directory is not owned by the current user and caching wheels has been\
disabled. check the permissions and owner of that directory. If executing pip with sudo, you may want sudo's -H flag.
/tmp/tmp6uv5w8/pip.zip/pip/_vendor/requests/packages/urllib3/util/ssl_.py:318: SNIMissingWarning: An HTTPS request has \
been made, but the SNI (Subject Name Indication) extension to TLS is not available on this platform. This may cause the\
server to present an incorrect TLS certificate, which can cause validation failures. You can upgrade to a newer versio\
n of Python to solve this. For more information, see https://urllib3.readthedocs.io/en/latest/security.html#snimissingw\
arning.
/tmp/tmp6uv5w8/pip.zip/pip/_vendor/requests/packages/urllib3/util/ssl_.py:122: InsecurePlatformWarning: A true SSLConte\
xt object is not available. This prevents urllib3 from configuring SSL appropriately and may cause certain SSL connecti\
ons to fail. You can upgrade to a newer version of Python to solve this. For more information, see https://urllib3.read\
thedocs.io/en/latest/security.html#insecureplatformwarning.
Requirement already up-to-date: pip in /usr/local/lib/python2.7/dist-packages
$ sudo -H pip install regex
sudo: unable to resolve host Ocean1
Collecting regex
/usr/local/lib/python2.7/dist-packages/pip/_vendor/requests/packages/urllib3/util/ssl_.py:318: SNIMissingWarning: An HT\
TPS request has been made, but the SNI (Subject Name Indication) extension to TLS is not available on this platform. Th\
is may cause the server to present an incorrect TLS certificate, which can cause validation failures. You can upgrade t\
o a newer version of Python to solve this. For more information, see https://urllib3.readthedocs.io/en/latest/security.\
html#snimissingwarning.
SNIMissingWarning
/usr/local/lib/python2.7/dist-packages/pip/_vendor/requests/packages/urllib3/util/ssl_.py:122: InsecurePlatformWarning:\
A true SSLContext object is not available. This prevents urllib3 from configuring SSL appropriately and may cause cert\
ain SSL connections to fail. You can upgrade to a newer version of Python to solve this. For more information, see http\
s://urllib3.readthedocs.io/en/latest/security.html#insecureplatformwarning.
InsecurePlatformWarning
Using cached regex-2017.01.17.tar.gz
Building wheels for collected packages: regex
Running setup.py bdist_wheel for regex ... ^[[?25lerror
Complete output from command /usr/bin/python -u -c "import setuptools, tokenize;__file__='/tmp/pip-build-qc8Myq/regex\
/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/tmpIm5vbcpip-wheel- --python-tag cp27:
/usr/local/lib/python2.7/dist-packages/setuptools/dist.py:333: UserWarning: Normalizing '2017.01.17' to '2017.1.17'
normalized_version,
running bdist_wheel
running build
running build_py
creating build
creating build/lib.linux-x86_64-2.7
copying Python2/regex.py -> build/lib.linux-x86_64-2.7
copying Python2/_regex_core.py -> build/lib.linux-x86_64-2.7
copying Python2/test_regex.py -> build/lib.linux-x86_64-2.7
running build_ext
building '_regex' extension
creating build/temp.linux-x86_64-2.7
creating build/temp.linux-x86_64-2.7/Python2
x86_64-linux-gnu-gcc -pthread -fno-strict-aliasing -DNDEBUG -g -fwrapv -O2 -Wall -Wstrict-prototypes -fPIC -I/usr/inc\
lude/python2.7 -c Python2/_regex.c -o build/temp.linux-x86_64-2.7/Python2/_regex.o
Python2/_regex.c:46:20: fatal error: Python.h: No such file or directory
#include "Python.h"
^
compilation terminated.
error: command 'x86_64-linux-gnu-gcc' failed with exit status 1
----------------------------------------
Failed building wheel for regex
^[[?25h Running setup.py clean for regex
Failed to build regex
Installing collected packages: regex
Running setup.py install for regex ... ^[[?25lerror
Complete output from command /usr/bin/python -u -c "import setuptools, tokenize;__file__='/tmp/pip-build-qc8Myq/reg\
ex/setup.py';f=getattr(tokenize, 'open', open)(__file__);code=f.read().replace('\r\n', '\n');f.close();exec(compile(cod\
e, __file__, 'exec'))" install --record /tmp/pip-oM77xP-record/install-record.txt --single-version-externally-managed -\
-compile:
/usr/local/lib/python2.7/dist-packages/setuptools/dist.py:333: UserWarning: Normalizing '2017.01.17' to '2017.1.17'
normalized_version,
running install
running build
running build_py
creating build
creating build/lib.linux-x86_64-2.7
copying Python2/regex.py -> build/lib.linux-x86_64-2.7
copying Python2/_regex_core.py -> build/lib.linux-x86_64-2.7
copying Python2/test_regex.py -> build/lib.linux-x86_64-2.7
running build_ext
building '_regex' extension
creating build/temp.linux-x86_64-2.7
creating build/temp.linux-x86_64-2.7/Python2
x86_64-linux-gnu-gcc -pthread -fno-strict-aliasing -DNDEBUG -g -fwrapv -O2 -Wall -Wstrict-prototypes -fPIC -I/usr/i\
nclude/python2.7 -c Python2/_regex.c -o build/temp.linux-x86_64-2.7/Python2/_regex.o
Python2/_regex.c:46:20: fatal error: Python.h: No such file or directory

This error message indicates that you are missing the Python development libraries.
Python2/_regex.c:46:20: fatal error: Python.h: No such file or directory
You can install them using the following command.
Windows Subsystem for Linux / Debian / Ubuntu
sudo apt-get install python-dev
Fedora / RedHat / CentOS
sudo yum install python-devel

You need to install the python-dev package, which includes Python.h.
There is a much simpler solution, though - install Python for Windows, without using the Linux Subsystem. Starting with Python 3.5 pip sometimes (actually, quite often) installs the precompiled binary version, saving you a lot of trouble.
In fact, since Python 3.5, it's easier to install most packages on Windows than it is on Linux.

It's because of you didn't have python-dev or python3-dev packages due to your python version.
Just install them through 'pip' or 'pip3' package installer and enjoy it!
Note if you find the mentioned packages is installed and your problem is still exist!, you must look for 'Python.h' file in your file system by:
sudo find / -name "Python.h"
and then add listed paths which includes Python.h into your C_INCLUDE_PATH environment variable something like:
export C_INCLUDE_PATH=/usr/include/python3.6m/
and now retry your installation and enjoy!

re (the regular expression package) comes with the regular python installation
re

pip install: Command clang failed [duplicate]

Python library gevent, version 0.13.6 (the current version on PyPI) will not pip install on OS X Lion, Python 2.7 (and probably others.) It works fine on Snow Leopard.
How can I get this library installed?
Bonus points if it can be done using pip install, rather than a manual or custom process, because then it will play nicely with automated builds.
Here is my pip install output:
pip install gevent
Downloading/unpacking gevent
Running setup.py egg_info for package gevent
Requirement already satisfied (use --upgrade to upgrade): greenlet in ./tl_env/lib/python2.7/site-packages (from gevent)
Installing collected packages: gevent
Running setup.py install for gevent
building 'gevent.core' extension
gcc-4.2 -fno-strict-aliasing -fno-common -dynamic -isysroot /Developer/SDKs/MacOSX10.6.sdk -arch i386 -arch x86_64 -g -O2 -DNDEBUG -g -O3 -I/Library/Frameworks/Python.framework/Versions/2.7/include/python2.7 -c gevent/core.c -o build/temp.macosx-10.6-intel-2.7/gevent/core.o
In file included from gevent/core.c:225:
gevent/libevent.h:9:19: error: event.h: No such file or directory
gevent/libevent.h:38:20: error: evhttp.h: No such file or directory
gevent/libevent.h:39:19: error: evdns.h: No such file or directory
gevent/core.c:361: error: field ‘ev’ has incomplete type
gevent/core.c:741: warning: parameter names (without types) in function declaration
gevent/core.c: In function ‘__pyx_f_6gevent_4core___event_handler’:
gevent/core.c:1619: error: ‘EV_READ’ undeclared (first use in this function)
gevent/core.c:1619: error: (Each undeclared identifier is reported only once
gevent/core.c:15376: warning: assignment makes pointer from integer without a cast
[... about 1000 more lines of compiler errors...]
gevent/core.c:15385: error: dereferencing pointer to incomplete type
gevent/core.c: In function ‘__pyx_pf_6gevent_4core_4http___init__’:
gevent/core.c:15559: warning: assignment makes pointer from integer without a cast
gevent/core.c: At top level:
gevent/core.c:21272: error: expected ‘)’ before ‘val’
lipo: can't figure out the architecture type of: /var/folders/s5/t94kn0p10hdgxzx9_9sprpg40000gq/T//cczk54q7.out
error: command 'gcc-4.2' failed with exit status 1
Complete output from command /Users/jacob/code/toplevel/tl_env/bin/python -c "import setuptools;__file__='/Users/jacob/code/toplevel/tl_env/build/gevent/setup.py';exec(compile(open(__file__).read().replace('\r\n', '\n'), __file__, 'exec'))" install --single-version-externally-managed --record /var/folders/s5/t94kn0p10hdgxzx9_9sprpg40000gq/T/pip-s2hPd3-record/install-record.txt --install-headers /Users/jacob/code/toplevel/tl_env/bin/../include/site/python2.7:
running install
running build
running build_py
running build_ext
building 'gevent.core' extension
gcc-4.2 -fno-strict-aliasing -fno-common -dynamic -isysroot /Developer/SDKs/MacOSX10.6.sdk -arch i386 -arch x86_64 -g -O2 -DNDEBUG -g -O3 -I/Library/Frameworks/Python.framework/Versions/2.7/include/python2.7 -c gevent/core.c -o build/temp.macosx-10.6-intel-2.7/gevent/core.o

Don't post the entire thing! That's too much! 90% of the time, the first error is enough...
gevent/libevent.h:9:19: error: event.h: No such file or directory
This means that the library which provides the event.h header is not installed. The library is called libevent (website).
In general, compilation errors like these are a flaw in the build scripts. The build script should give an error message that libevent is not installed, and it is a bug that it did not do so.
To get libevent from MacPorts and then manually tell compiler with CFLAGS environment variable where to find event.h and libevent while running pip.
sudo port install libevent
CFLAGS="-I /opt/local/include -L /opt/local/lib" pip install gevent
You can also use homebrew for installing libevent : brew install libevent
(from David Wolever's comment)

CFLAGS='-std=c99' pip install gevent
See in: Can't install gevent OSX 10.11
on OS X 10.11, clang uses c11 as the default, so just turn it back to c99.

After a while, I realized that the paths for the CFLAGS variable mentioned above works when installing libevent from port, but not from brew. The following worked for me (on OSX Mavericks):
$ brew install libevent
$ export CFLAGS="-I /usr/local/Cellar/libevent/2.0.21/include -L /usr/local/Cellar/libevent/2.0.21/lib"
$ pip install gevent

This is the way I found the easiest:
install libevent using homebrew
$ brew install libevent
install gevent
$ pip install gevent
This was the only way I could get it to work.

Found this answer when looking for help installing on Snow Leopard, posting this in case someone else comes this way with the same problem.
I had libevent installed via macports.
export CFLAGS=-I/opt/local/include
export LDFLAGS=-L/opt/local/lib
sudo pip install gevent

I had libevent installed via brew and it failed too, what worked was similar to what Stephen done, but pointing to brew default install:
CFLAGS=-I/usr/local/include LDFLAGS=-L/usr/local/lib pip install gevent

In case you install all from sources and use csh the following works on mac os 10.9
download latest stable http://libevent.org/ libevent-2.0.21-stable
./configure
make
sudo make install
virtualenv env
source env/bin/activate.csh
setenv CFLAGS "-I /usr/local/include -L /usr/local/lib"
pip install gevent

I use virtualenv and virtualenv wrapper, and so I wanted this to be self contained. I got gevent working like so:
Assuming you have virtual env setup, then:
workon {my_virtual_env}
Then download libevent and install it against the virtualenv.
curl -L -O https://github.com/downloads/libevent/libevent/libevent-2.0.21-stable.tar.gz
tar -xzf libevent-2.0.21-stable.tar.gz
cd libevent-2.0.21-stable
./configure --prefix="$VIRTUAL_ENV"
make && make install
I'm assuming you've got gcc 5+ installed (I use brew)
Hope this helps.

sudo pip install cython git+git://github.com/gevent/gevent.git#egg=gevent

I am using MacOs High Sierra (10.13.3)
First I did :
brew install libevent
I upgraded my pip version to pip-18.0.
then tried installing again with following :-
pip install gevent
it worked.

How can I install the Python library 'gevent' on Mac OS X Lion

Python library gevent, version 0.13.6 (the current version on PyPI) will not pip install on OS X Lion, Python 2.7 (and probably others.) It works fine on Snow Leopard.
How can I get this library installed?
Bonus points if it can be done using pip install, rather than a manual or custom process, because then it will play nicely with automated builds.
Here is my pip install output:
pip install gevent
Downloading/unpacking gevent
Running setup.py egg_info for package gevent
Requirement already satisfied (use --upgrade to upgrade): greenlet in ./tl_env/lib/python2.7/site-packages (from gevent)
Installing collected packages: gevent
Running setup.py install for gevent
building 'gevent.core' extension
gcc-4.2 -fno-strict-aliasing -fno-common -dynamic -isysroot /Developer/SDKs/MacOSX10.6.sdk -arch i386 -arch x86_64 -g -O2 -DNDEBUG -g -O3 -I/Library/Frameworks/Python.framework/Versions/2.7/include/python2.7 -c gevent/core.c -o build/temp.macosx-10.6-intel-2.7/gevent/core.o
In file included from gevent/core.c:225:
gevent/libevent.h:9:19: error: event.h: No such file or directory
gevent/libevent.h:38:20: error: evhttp.h: No such file or directory
gevent/libevent.h:39:19: error: evdns.h: No such file or directory
gevent/core.c:361: error: field ‘ev’ has incomplete type
gevent/core.c:741: warning: parameter names (without types) in function declaration
gevent/core.c: In function ‘__pyx_f_6gevent_4core___event_handler’:
gevent/core.c:1619: error: ‘EV_READ’ undeclared (first use in this function)
gevent/core.c:1619: error: (Each undeclared identifier is reported only once
gevent/core.c:15376: warning: assignment makes pointer from integer without a cast
[... about 1000 more lines of compiler errors...]
gevent/core.c:15385: error: dereferencing pointer to incomplete type
gevent/core.c: In function ‘__pyx_pf_6gevent_4core_4http___init__’:
gevent/core.c:15559: warning: assignment makes pointer from integer without a cast
gevent/core.c: At top level:
gevent/core.c:21272: error: expected ‘)’ before ‘val’
lipo: can't figure out the architecture type of: /var/folders/s5/t94kn0p10hdgxzx9_9sprpg40000gq/T//cczk54q7.out
error: command 'gcc-4.2' failed with exit status 1
Complete output from command /Users/jacob/code/toplevel/tl_env/bin/python -c "import setuptools;__file__='/Users/jacob/code/toplevel/tl_env/build/gevent/setup.py';exec(compile(open(__file__).read().replace('\r\n', '\n'), __file__, 'exec'))" install --single-version-externally-managed --record /var/folders/s5/t94kn0p10hdgxzx9_9sprpg40000gq/T/pip-s2hPd3-record/install-record.txt --install-headers /Users/jacob/code/toplevel/tl_env/bin/../include/site/python2.7:
running install
running build
running build_py
running build_ext
building 'gevent.core' extension
gcc-4.2 -fno-strict-aliasing -fno-common -dynamic -isysroot /Developer/SDKs/MacOSX10.6.sdk -arch i386 -arch x86_64 -g -O2 -DNDEBUG -g -O3 -I/Library/Frameworks/Python.framework/Versions/2.7/include/python2.7 -c gevent/core.c -o build/temp.macosx-10.6-intel-2.7/gevent/core.o

Don't post the entire thing! That's too much! 90% of the time, the first error is enough...
gevent/libevent.h:9:19: error: event.h: No such file or directory
This means that the library which provides the event.h header is not installed. The library is called libevent (website).
In general, compilation errors like these are a flaw in the build scripts. The build script should give an error message that libevent is not installed, and it is a bug that it did not do so.
To get libevent from MacPorts and then manually tell compiler with CFLAGS environment variable where to find event.h and libevent while running pip.
sudo port install libevent
CFLAGS="-I /opt/local/include -L /opt/local/lib" pip install gevent
You can also use homebrew for installing libevent : brew install libevent
(from David Wolever's comment)

CFLAGS='-std=c99' pip install gevent
See in: Can't install gevent OSX 10.11
on OS X 10.11, clang uses c11 as the default, so just turn it back to c99.

After a while, I realized that the paths for the CFLAGS variable mentioned above works when installing libevent from port, but not from brew. The following worked for me (on OSX Mavericks):
$ brew install libevent
$ export CFLAGS="-I /usr/local/Cellar/libevent/2.0.21/include -L /usr/local/Cellar/libevent/2.0.21/lib"
$ pip install gevent

This is the way I found the easiest:
install libevent using homebrew
$ brew install libevent
install gevent
$ pip install gevent
This was the only way I could get it to work.

Found this answer when looking for help installing on Snow Leopard, posting this in case someone else comes this way with the same problem.
I had libevent installed via macports.
export CFLAGS=-I/opt/local/include
export LDFLAGS=-L/opt/local/lib
sudo pip install gevent

I had libevent installed via brew and it failed too, what worked was similar to what Stephen done, but pointing to brew default install:
CFLAGS=-I/usr/local/include LDFLAGS=-L/usr/local/lib pip install gevent

In case you install all from sources and use csh the following works on mac os 10.9
download latest stable http://libevent.org/ libevent-2.0.21-stable
./configure
make
sudo make install
virtualenv env
source env/bin/activate.csh
setenv CFLAGS "-I /usr/local/include -L /usr/local/lib"
pip install gevent

I use virtualenv and virtualenv wrapper, and so I wanted this to be self contained. I got gevent working like so:
Assuming you have virtual env setup, then:
workon {my_virtual_env}
Then download libevent and install it against the virtualenv.
curl -L -O https://github.com/downloads/libevent/libevent/libevent-2.0.21-stable.tar.gz
tar -xzf libevent-2.0.21-stable.tar.gz
cd libevent-2.0.21-stable
./configure --prefix="$VIRTUAL_ENV"
make && make install
I'm assuming you've got gcc 5+ installed (I use brew)
Hope this helps.

sudo pip install cython git+git://github.com/gevent/gevent.git#egg=gevent

I am using MacOs High Sierra (10.13.3)
First I did :
brew install libevent
I upgraded my pip version to pip-18.0.
then tried installing again with following :-
pip install gevent
it worked.