Install SAS on Linux (OpenSUSE Leap 423)

h1. Install SAS on Linux (OpenSUSE Leap 42.3)

(as of 11/2017)
Also see  Install HEASOFT on Linux (OpenSUSE Leap 4.23)

Based on https://www.cosmos.esa.int/web/xmm-newton/sas-requirements

```
	PERL:
		install perl 5.22.2 	via "perlbrew" https://perlbrew.pl/
			- YaST2-OpenSUSE doesn't have that version (only 5.18.2-7.15) !	not even in http://download.OpenSUSE.org/repositories/devel:/languages:/perl/
			- "install SAS 16.1.0 with SAS_PERL pointing to the Perl 5.22.2 binary provided by such installation."
	.
			install perlbrew (Release 0.79): 16.11.2017
				curl -L https://install.perlbrew.pl | bash
	.
			install perl 5.22.2 via perlbrew:
				source ~/perl5/perlbrew/etc/cshrc	-> add to .tcshrc
				perlbrew install perl-5.22.2		-> see ~/perl5/perlbrew/build.perl-5.22.2.log
				perlbrew switch perl-5.22.2
	.
		PATH: ~/perl5/perlbrew/perls/perl-5.22.2/bin/perl

	DS9:
		install ds9 	>7.4 and  http://ds9.si.edu/site/Download.html 7.5 (Dec 15, 2016) [or via YaST2-OpenSUSE (7.5-1.2)]
			ds9.ubuntu16.7.5.tar.gz		->  http://ds9.si.edu/site/Download.html
			-> just unpacked with tar -zxvpf
	.
		install xpa 2.1.17  (Dec 15, 2016) http://ds9.si.edu/site/XPA.html
			-> just unpacked with tar -zxvpf
			- http://hea-www.harvard.edu/RD/xpa/
	.
			xpa.ubuntu16.2.1.17.tar.gz  -> http://ds9.si.edu/site/XPA.html
	.
		ISSUE: "XPA unable to verify hostname, setting XPA_METHOD to LOCAL" when executing ds9
		Solutions:
			- https://github.com/mmechtley/OSX-DS9-Shell/pull/1#issuecomment-58487979
			- https://community.lsst.org/t/ds9-communication-via-xpa/2242
		1) start "./ds9 -xpa local" instead of "./ds9"
		2) add "setenv XPA_METHOD local" into .tcshrc
			or "export XPA_METHOD=local" into .bashrc
	.
		PATH: ~/Software/Science/ds9_xpa_for_SAS/..
		- Create soft-link: sudo ln -s ~/Software/Science/ds9_xpa_for_SAS/ds9 /usr/bin/

	GRACE
		need Grace 5.1.25	ftp://plasma-gate.weizmann.ac.il/pub/grace/src/stable/grace-5.1.25.tar.gz
		installed via YaST2-OpenSUSE: "xmgrace"  version 5.1.25-4.14 - Jul 8 00:56:38 2017
	.
		PATH:  /usr/bin/xmgrace

	WCSTOOLS
		need WCSTools Version 3.9.4 (April 13, 2011) ftp://cfa-ftp.harvard.edu/pub/gsc/WCSTools/index.html (not in YaST2-OpenSUSE)
		installed -> Version 3.9.5 (March 30, 2017)
		- downloaded  wcstools-3.9.5.tar.gz via ftp://cfa-ftp.harvard.edu/pub/gsc/WCSTools/
		- unpacked with tar -zxvpf
		- source ~/perl5/perlbrew/etc/cshrc
		- perlbrew switch perl-5.22.2
		- cd wcstools-3.9.5)
		- make all
		done
	.
		PATH: ~/Software/Science/wcstools/wcstools-3.9.5

	HEATOOLS
		needed version 6.19
		installed version 6.22.1 (inlc. Xspec v12.9.1p)
		-> see ~/Software/Science/heasoft/How2build.txt
	.
		PATH: ~/Software/Science/heasoft/heasoft_current/x86_64-unknown-linux-gnu-libc2.22

	SAS:
		download: https://www.cosmos.esa.int/web/xmm-newton/sas-download
			Build on 		Kernel version 	libc version 	File to download
		USE	RHEL6.8 		2.6.32 		2.12 		sas_16.1.0-RHEL6.8-64.tgz
			Ubuntu16.04.1LTS 	4.4.0 		2.23 		sas_16.1.0-Ubuntu16.04-64.tgz		-> OpenSUSE Leap 42.3 doesn't have yet glbic 2.23 (only 2.22)
			"For the latest Linux distributions as for example Ubuntu 17.04, Fedora 26, OpenSUSE Leap 42.3, etc, we recommend to install the build made on Ubuntu 16.04.1LTS."
	.
		install: - https://www.cosmos.esa.int/web/xmm-newton/sas-installation
		- cd ~/Software/Science/SAS
		- tar -zxvpf sas_16.1.0-Ubuntu16.04-64.tgz
		- setenv SAS_PERL ~/perl5/perlbrew/perls/perl-5.22.2/bin/perl
		- ./install.sh
		- ln -s ~/Software/Science/SAS/xmmsas_20170719_1539 sas_current
		DONE
	.
		Initialization: add source ~/Software/Science/SAS/sas_current/setsas.csh in .tcshrc
		(after HEATOOLS)
	.
	Problem:
		OpenSUSE Leap 42.3
		sasversion: /lib64/libm.so.6: version `GLIBC_2.23' not found (required by ~/Software/Science/SAS/xmmsas_20170719_1539/libextra/libquadmath.so.0)
	.
		Also see: http://xmm2.esac.esa.int/xmmhelp/SASv16.0_Installation?id=81843;user=guest
	.
		-> OpenSUSE Leap 42.3 has only verson GLIBC 2.22
	.
		Solution: install sas_16.1.0-RHEL6.8-64.tgz instead with glibc 2.12
	.
		Set soft-links:
		ln -s ~/Software/Science/SAS/xmmsas_20170719_1539_glibc2.12 xmmsas_20170719_1539	-> needed by SAS
		ln -s ~/Software/Science/SAS/xmmsas_20170719_1539 sas_current				-> used by .tcshrc

	PENDING
		install pyds9 "pyds9 module uses a Python interface to XPA to communicate with ds9" (not in YaST2-OpenSUSE)
			http://hea-www.harvard.edu/RD/pyds9/
			https://github.com/ericmandel/pyds9/blob/master/README.md

```