Install mono on centOS 6.x

install_mono.sh

$ yum install bison gettext glib2 freetype fontconfig libpng libpng-devel libX11 libX11-devel glib2-devel libgdi* libexif glibc-devel urw-fonts java unzip gcc gcc-c++ automake autoconf libtool make bzip2 wget

$ cd /usr/local/src 

$ wget http://download.mono-project.com/sources/mono/mono-3.2.8.tar.bz2

$ tar jxf mono-3.2.8.tar.bz2

$ cd mono-3.2.8

$ ./configure --prefix=/opt/mono

$ make && make install

$ export PATH=$PATH:/opt/mono/bin
$ export PKG_CONFIG_PATH=/opt/mono/lib/pkgconfig
$ # make sure to add the previous two lines to your ~/.bash_profile

Works for Mono 3.12.1 on CentOS 6.3...

Wow! works Mono 4.2.2.30 on CentOS 6.3.. Great

@kimhs20 which monolite version have you used? I get this error all the time:

*** The compiler 'mcs' doesn't appear to be usable.
*** Trying the 'monolite' directory.
Bootstrap compiler: Mono C# compiler version 4.3.2.0
./../jay/jay: 8 shift/reduce conflicts.
mkdir -p -- ../class/lib/basic/
MCS     [basic] basic.exe
warning CS8001: SDK path could not be resolved
warning CS1685: The predefined type 'System.Security.Permissions.HostProtectionAttribute' is defined multiple times. Using definition from 'mscorlib.dll'
/usr/local/src/mono-4.2.2/mcs/class/lib/monolite/mscorlib.dll (Location of the symbol related to previous warning)
/usr/local/src/mono-4.2.2/mcs/class/lib/monolite/System.dll (Location of the symbol related to previous warning)

Unhandled Exception:
System.InvalidCastException: Arg_InvalidCastException
  at System.Collections.Generic.EnumEqualityComparer'1[T].Equals (T x, T y) <0x41339f80 + 0x00046> in <filename unknown>:0
  at System.Collections.Generic.List'1[T].Contains (System.Collections.Generic.T item) <0x413393f0 + 0x0009f> in <filename unknown>:0
  at Mono.CSharp.TypeDefinition.CheckPairedOperators () <0x41338e40 + 0x0014b> in <filename unknown>:0
  at Mono.CSharp.TypeDefinition.DoDefineMembers () <0x4131cb70 + 0x00c67> in <filename unknown>:0
  at Mono.CSharp.ClassOrStruct.DoDefineMembers () <0x4131c6e0 + 0x0022f> in <filename unknown>:0
  at Mono.CSharp.Class.DoDefineMembers () <0x4131c000 + 0x0068f> in <filename unknown>:0
  at Mono.CSharp.TypeDefinition.Define () <0x4131bad0 + 0x0002c> in <filename unknown>:0
  at Mono.CSharp.TypeContainer.Define () <0x4131b9e0 + 0x0005a> in <filename unknown>:0
  at Mono.CSharp.TypeContainer.Define () <0x4131b9e0 + 0x0005a> in <filename unknown>:0
  at Mono.CSharp.TypeContainer.Define () <0x4131b9e0 + 0x0005a> in <filename unknown>:0
  at Mono.CSharp.ModuleContainer.Define () <0x41304c00 + 0x00027> in <filename unknown>:0
  at Mono.CSharp.Driver.Compile () <0x412496b0 + 0x00634> in <filename unknown>:0
  at Mono.CSharp.Driver.Main (System.String[] args) <0x4121ce00 + 0x00173> in <filename unknown>:0

just succeed to make mono-4.4.0.40 with monolite 140: http://download.mono-project.com/monolite/monolite-140-latest.tar.gz

it was required to install monolite right after configure ( "./autogen.sh --prefix=/opt/mono" ):

make get-monolite-latest monolite_url=http://download.mono-project.com/monolite/monolite-140-latest.tar.gz

P.S. CentOS 6.7

The installation worked with Mono 4.2.3.4 on RHEL 6. Thank you!
I am a newbie at Linux. I'd like to compile a C# code just to test my Mono installation. If I type, $ cms HelloWorld.cs from a terminal window, I am getting an error message "bash: cms: command not found". How can I start Mono? Please help.

Dear all,
I can finish the install setup in Centos6.6, but I can not run aspx website in apache
https://drive.google.com/file/d/0BxriXuT0xeaFcl9KOGZ2YXROYUk/view?usp=sharing
Or how can we setup mono for aspx file normal running in Centos? Thanks a lot.

I was able to to install mono 4.9 and xsp 4.2. on CentOS release 6.8 (Final) based on your instructions, thanks!

I also got the error I got an error about LIBGDIPLUS not found because for some reason this would not install. I installed it from

http://download.mono-project.com/sources/libgdiplus/

using the commands below and it ran successfully.

cd /usr/local/src
wget http://download.mono-project.com/sources/libgdiplus/libgdiplus-4.2.tar.gz
tar zxvf libgdiplus-4.2.tar.gz
cd libgdiplus-4.2
./configure --prefix=/opt/mono
make && make install

Hope this helps someone else and thanks again.

I was able to install mono 4.4.0.40 on centOS 6.0

I was able to install mono mono-4.8.1.0 like a charm. Thank you!

❗ Edit

I just found out that mono can be installed on CentOS 6 without building it ourselves.
https://www.mono-project.com/download/stable/#download-lin-centos

# Add repo
rpm --import "https://keyserver.ubuntu.com/pks/lookup?op=get&search=0x3FA7E0328081BFF6A14DA29AA6A19B38D3D831EF"
su -c 'curl https://download.mono-project.com/repo/centos6-stable.repo | tee /etc/yum.repos.d/mono-centos6-stable.repo'

# Install mono
yum install mono-complete