30 Appendix A: Install and Build ROOT

30.1 License

ROOT is made available under the LGPL v2.1 license. For full details see the file LICENSE in the ROOT distribution.

30.2 Installing ROOT

To install ROOT you will need to go to the ROOT website at: http://root.cern.ch/drupal/content/downloading-root

You have a choice to download the binaries or the source. The source is quicker to transfer since it is only 31 MB, but you will need to compile and link it. The binaries range from 50 MB to 100 MB depending on the target platform.

30.3 Choosing a Version

The ROOT developers follow the principle of “release early and release often”, however a very large portion of a user base requires a stable product therefore generally three versions of the system is available for download - new, old and pro:

30.4 Installing Precompiled Binaries

The binaries are available for downloading from http://root.cern.ch/drupal/content/downloading-root. Once downloaded you need to unzip and de-tar the file. For example, if you have downloaded ROOT v5.30 for Linux-SLC5:

% gunzip root_v5.30.00.Linux-slc5-gcc4.3.tar.gz
% tar xvf root_v5.30.00.Linux-slc5-gcc4.3.tar

This will create the directory root. Before getting started read the file README/README. Also, read the Introduction chapter for an explanation of the directory structure.

30.5 Installing the Source

You have a choice to download a compressed (tar ball) file containing the source, or you can use the Subversion (svn) source code change control system and check out the most recent source. The compressed file is a one time only choice; every time you would like to upgrade you will need to download the entire new version. Choosing the CVS option will allow you to get changes as they are submitted by the developers and you can stay up to date.

30.5.1 Installing and Building the Source from a Compressed File

To install the ROOT source you can download the tar file containing all the source files from the ROOT website. The first thing you should do is to get the latest version as a tar file. Unpack the source tar file, this creates directory ‘root’:

% tar zxvf root_v5.30.xx.source.tar.gz

Type the build commands:

% cd root
% ./configure --help
% ./configure [<arch>]
% (g)make

Add bin/ to PATH and lib/ to LD_LIBRARY_PATH. For the sh shell family do:

% . bin/thisroot.sh

and for the csh shell family do:

% source bin/thisroot.csh

Try running root:

% root

It is also possible to setup and build ROOT in a fixed location. Please check README/INSTALL for more a detailed description of this procedure. Target directory

By default, ROOT will be built in the $ROOTSYS directory. In that case the whole system (binaries, sources, tutorials, etc.) will be located under the $ROOTSYS directory. Makefile targets

The Makefile is documented in details in the README/BUILDSYSTEM file. It explains the build options and targets.

30.5.2 More Build Options

To build the library providing thread support you need to define either the environment variable ‘THREAD=-lpthread'or the configure flag ‘--with-thread=-lpthread’ (it is the default for the linuxegcs architecture). [Note: this is only tested on Linux for the time being.] To build the library providing CERN RFIO (remote I/O) support you need to define either the environment variable ‘ RFIO=<path>/libshift.a’ or the configure flag ‘--with-rfio=<path>/libshift.a'. For pre-built version of libshift.a see ftp://root.cern.ch/root/shift/

To build the PAW and Geant3 conversion programs h2root and g2root you need to define either the environment variable ‘CERNLIB=<cernlibpath>‘or the configure flag ‘--with-cern-libdir=<cernlibpath>’.

To build the MySQL interface library you need to install MySQL first. Visit http://www.mysql.com/ for the latest versions.

To build the strong authentication module used by rootd, you first have to install the SRP (Secure Remote Password) system. Visit http://srp.stanford.edu

To use the library you have to define either the environment variable ‘SRP=<srpdir>’ or the configure flag ‘--with-srp=<srpdir>'.

To build the event generator interfaces for Pythia and Pythia6, you first have to get the Pythia libraries available from ftp: ftp://root.cern.ch/root/pythia6.tar.gz.

To use the libraries you have to define either ‘PYTHIA=<pythiadir>’ or the configure flag ‘--with-pythia=<pythiadir>’. The same applies for Pythia6. Installing the Source from Subversion

This paragraph describes how to checkout and build ROOT from Subversion for Unix systems. For description of a checkout for other platforms, please see ROOT installation web page: http://root.cern.ch/drupal/content/installing-root-source.

% svn co http://root.cern.ch/svn/root/trunk root
U root/...
U ...
% cd root
% ./configure --help
% ./configure [<arch>]
% (g)make

If you are a part of collaboration, you may need to use setup procedures specific to the particular development environment prior to running (g)make. For more install instructions and options, see the file README/INSTALL. Subversion for Windows

Although there exists a native version of Subversion for Windows, we only support the build process under the Cygwin environment. You must have svn version 1.6 or newer. The checkout and build procedure is similar to that for UNIX. For detailed install instructions, see the file REAMDE/INSTALL. Staying up-to-date

To keep your local ROOT source up-to-date with the Subversion repository you should regularly run the command:

% svn up

30.6 File system.rootrc

ROOT Environment settings are handled via the class TEnv. gEnv->Print()shows which values are active. Any settings can be obtained by TEnv::GetValue methods that return an integer, double or character value for a named resource. If the resource is not found, the default value (given as the second parameter) is returned.

fShowEventStatus = gEnv->GetValue("Canvas.ShowEventStatus",kFALSE);

Via the method TEnv::SetValue allows you can set the value of a resource or create a new resource:


Path used by dynamic loader to find shared libraries and macros. Paths are different for Unix and Windows. The example shows the defaults for all ROOT applications for either Unix or Windows:

Unix.*.Root.DynamicPath:    .:$(ROOTSYS)/lib
Unix.*.Root.MacroPath:      .:$(ROOTSYS)/macros
WinNT.*.Root.DynamicPath:   .;$(ROOTSYS)/bin;$(PATH)
WinNT.*.Root.MacroPath:     .;$(ROOTSYS)/macros

Path where to look for TrueType fonts:

Unix.*.Root.UseTTFonts:     true
*.*.Root.TTFontPath:        $(ROOTSYS)/fonts

Use Net* API functions:

WinNT.UseNetAPI:            true

Use thread library (if exists).

Unix.*.Root.UseThreads:     false

Select the compression algorithm (0=old zlib, 1=new zlib). Setting this to `0’ may be a security vulnerability.

Root.ZipMode:               1

Show where item is found in the specified path:

Root.ShowPath:              false

Activate memory statistics (size and cnt are used to trap allocation of blocks of a certain size after cnt attempts).

Root.MemStat:               0
Root.MemStat.size:         -1
Root.MemStat.cnt:          -1
Root.ObjectStat:            0

Activate memory leak checker (use in conjunction with $ROOTSYS/bin/memprobe). Currently only works on Linux with gcc.

Root.MemCheck:              0
Root.MemCheckFile:          memcheck.out

Global debug mode. When >0 turns on progressively more details debugging.

Root.Debug:                 0
Root.Stacktrace:            yes

Settings for X11 behaviour.

X11.Sync:                   no
X11.FindBestVisual:         yes

Default editor in use.

Unix.*.Editor:              vi
WinNT.*.Editor:             notepad

Default 3d Viewer. By default 3-D views are shown in the pad, if the next line is activated, the default viewer will be OpenGL.

Viewer3D.DefaultDrawOption: ogl

Default Fitter (current choices are Minuit, Minuit2, Fumili and Fumili2).

Root.Fitter:                Minuit

Specify list of file endings which TTabCom (TAB completion) should ignore.

TabCom.FileIgnore:          .cpp:.h:.cmz

30.6.1 TCanvas Specific Settings

Opaque move and resize show full pad during the operation instead of only the outline. Especially for resize you will need serious CPU power. UseScreenFactor=true means to size canvas according to size of screen, so a canvas still looks good on a low resolution laptop screen without having to change canvas size in macros.

Canvas.MoveOpaque:          false
Canvas.ResizeOpaque:        false
Canvas.UseScreenFactor:     true

Hight color 2 is the red one.

Canvas.HighLightColor:      2

Next three settings are related to different user interface parts of canvas window. If they are set to true, the corresponding event status bar, tool bar, graphics editor to beactivated by default.

Canvas.ShowEventStatus:     false
Canvas.ShowToolBar:         false
Canvas.ShowEditor:          false

AutoExec allows TExec objects to be executed on mouse and key events.

Canvas.AutoExec:            true

Canvas print directory is set to the current one by default:

Canvas.PrintDirectory     .

Printer settings:

WinNT.*.Print.Command:    AcroRd32.exe
#Unix.*.Print.Command:    a2ps -P%p --landscape --columns=2 --margin=30 -rf8.0 %f
Print.Printer:            32-rb20-hp
Print.Directory:          .
Print.FileType:           pdf

Default histogram binnings used by TTree::Draw() method.

Hist.Binning.1D.x:          100
Hist.Binning.2D.x:           40
Hist.Binning.2D.y:           40
Hist.Binning.2D.Prof:       100
Hist.Binning.3D.x:           20
Hist.Binning.3D.y:           20
Hist.Binning.3D.z:           20
Hist.Binning.3D.Profx:      100
Hist.Binning.3D.Profy:      100

Default statistics names used for parameters in TPaveStats:

Hist.Stats.Entries         Entries
Hist.Stats.Mean            Mean
Hist.Stats.MeanX           Mean x
Hist.Stats.MeanY           Mean y
Hist.Stats.RMS             RMS
Hist.Stats.RMSX            RMS x
Hist.Stats.RMSY            RMS y
Hist.Stats.Underflow       Underflow
Hist.Stats.Overflow        Overflow
Hist.Stats.Integral        Integral
Hist.Stats.Skewness        Skewness
Hist.Stats.SkewnessX       Skewness x
Hist.Stats.SkewnessY       Skewness y
Hist.Stats.Kurtosis        Kurtosis
Hist.Stats.KurtosisX       Kurtosis x
Hist.Stats.KurtosisY       Kurtosis y

30.6.2 THtml Specific Settings

See the reference guide documentation of THtml class at http://root.cern.ch/root/htmldoc/THtml.html for more details.

XHTML content charset (see http://www.w3.org/TR/2002/REC-xhtml1-20020801, default: ISO-8859-1) is set by:


Stem of a search engine for the documentation, where %s is replaced by the term entered in the search text box (example: http://www.google.com/search?q=%s+site%3Aroot.cern.ch%2Froot%2Fhtml, default is "")


Link to the site’s search engine (default: "", example: http://root.cern.ch/root/Search.phtml)


String to prepend to TClass::GetImplFileName() names containing directories when looking for source files (default: "", example: ../root)


Link stem to ViewCVS entry for classes, where a class name is assumed to match a file name (default: "", example: http://root.cern.ch/viewcvs).


Stem of the CERN XWho system (default: http://consult.cern.ch/xwho/people?)


If set to Doc++, allow method documentation in front of method even for methods in the source file (default: "")


Search path for the source and header files with their default settings:

Unix.*.Root.Html.SourceDir:  .:src:include
WinNT.*.Root.Html.SourceDir: .;src;include

URL stem for ROOT documentation pages (default is "").

Root.Html.Root:              http://root.cern.ch/root/html

Filesystem output directory for generated web pages (default: htmldoc).

Root.Html.OutputDir:        htmldoc/

Address of the package’s home page (default: http://root.cern.ch):


Location of user defined header and footer files, see http://root.cern.ch/root/html/THtml#conf:header (defaults are "", example: ../header.txt, ../footer.txt):


Tag for detecting class description comments (default value is set below).

Root.Html.Description:      //____________________

Tag for detecting “Author” comment (default value is set below).

Root.Html.Author:           // Author:

Tag for detecting “last updated” comment. THtml uses the current date if this tag is not found in a class source file (default value is set below).

Root.Html.LastUpdate:       // @(#)

Tag for detecting “Copyright” comment (default value is set below).

Root.Html.Copyright:        * Copyright

30.6.3 GUI Specific Settings

Set the “native” ROOT GUI interface to be used in a ROOT session. If set to “qt”, the “native” GUI interface is replaced with one based on Qt by the regular ROOT plug-in mechanism.

Gui.Backend:                native
Gui.Factory:                native

GUI default fonts in use:

Gui.DefaultFont:            -adobe-helvetica-medium-r-*-*-12-*-*-*-*-*-iso8859-1
Gui.MenuFont:               -adobe-helvetica-medium-r-*-*-12-*-*-*-*-*-iso8859-1
Gui.MenuHiFont:             -adobe-helvetica-bold-r-*-*-12-*-*-*-*-*-iso8859-1
Gui.DocFixedFont:           -adobe-courier-medium-r-*-*-12-*-*-*-*-*-iso8859-1
Gui.DocPropFont:            -adobe-helvetica-medium-r-*-*-12-*-*-*-*-*-iso8859-1
Gui.IconFont:               -adobe-helvetica-medium-r-*-*-10-*-*-*-*-*-iso8859-1
Gui.StatusFont:             -adobe-helvetica-medium-r-*-*-10-*-*-*-*-*-iso8859-1

Regular background and foreground colors in use:

Gui.BackgroundColor:         #c0c0c0
Gui.ForegroundColor:         black

Selection background and foreground colors in use:

Gui.SelectBackgroundColor:   #000080
Gui.SelectForegroundColor:   white

Document background and foreground colors in use:

Gui.DocumentBackgroundColor: white
Gui.DocumentForegroundColor: black

Tooltip background and foreground colors in use:

Gui.TooltipBackgroundColor:  LightYellow
Gui.TooltipForegroundColor:  black

Path where all GUI icons in use can be found:

Gui.IconPath:                $(HOME)/icons:$(ROOTSYS)/icons:.

Mime type file setting:

Gui.MimeTypeFile:            $(HOME)/.root.mimes

If $(HOME)/.root.mimes does not exists, defaults to this:

#Gui.MimeTypeFile:            $(ROOTSYS)/etc/root.mimes

30.6.4 TBrowser Settings

Current icon style selection - can be either small, big, list, details:

Browser.IconStyle:           small

Current sorting rule applied on the browser objects - can be name, type, size, date:

Browser.SortBy:              name

Number of items in a group view:

Browser.GroupView:           10000

Show or not hidden items:

Browser.ShowHidden:          no

Create a thumbnail view after executing the macro (default is yes).

Browser.AutoThumbnail:       yes

30.6.5 TRint Specific Settings

Rint (interactive ROOT executable) specific alias, logon and logoff macros.

Rint.Load:               rootalias.C
Rint.Logon:              rootlogon.C
Rint.Logoff:             rootlogoff.C

Record ROOT session commands in a given history file (default is $(HOME)/.root_hist). If set to “-”, it turn off the command recording.

Rint.History:            $(HOME)/.root_hist

Next two lines set the history file size handling. Once HistSize is reached, the last HistSave entries are removed. If HistSize is set to 0, it turns off command recording. Both values can be overridden by environment variable ROOT_HIST=size[:save], where the “:save” part is optional.

Rint.HistSize:         500
Rint.HistSave:         400

30.6.6 ACLiC Specific Settings

ACLiC.Linkdef specifies the suffix that will be added to the script name to try to locate a custom linkdef file when generating the dictionary.

ACLiC.Linkdef:          _linkdef

The top directory for storing the libraries produced by ACLiC is set by:

ACLiC.BuildDir:        /where/I/would/like/my/compiled/scripts

The additional include directives for ACLiC compilations are set by:

ACLiC.IncludePaths:     -I/where/the/includes/are

PROOF debug options.

Proof.DebugLevel: 0

PROOF GDB hooks allows a debugger to be attached early in the startup phase of proofserv:0 - don’t wait; 1 - master proofserv enters wait loop; 2 - slave proofserv enters wait loop; 3 - any proofserv enters wait loop

Proof.GdbHook:    0

On the master to enable the parallel startup of workers using threads set next to “yes” (default is “no”):

Proof.ParallelStartup: no
Proof.StatsHist:       no
Proof.StatsTrace:      no
Proof.SlaveStatsTrace: no
Proof.CondorHome:     /opt/condor
Proof.CondorConfig:   /opt/condor/etc/condor_config
PEAC.GmUrl:           http://somewhere:8080/clarens/
PEAC.LmUrl:           http://elsewhere:8080/clarens/

Certificate and key

Clarens.CertFile:     $(HOME)/.globus/usercert.pem
Clarens.KeyFile:      $(HOME)/.globus/userkey.pem

Default authentication method for rootd and proofd. These are supported for backward compatibility but have a very low priority. System defaults are generated by configure as a list in system.rootauthrc in $ROOTSYS/etc/ or /etc/root; the file $HOME/.rootauthrc can be used to override the system defaults.

The value meaning: 0=UsrPwd, 1=SRP, 2=Krb5, 3=Globus,4=SSH, 5=UidGid.

Rootd.Authentication:    0
Proofd.Authentication:   0

Connection is shutdown at timeout expiration. Timeout is in seconds. Negotiation cannot be attempted at low level (i.e. inside TAuthenticate::Authenticate()) because of synchronization problems with the server. At higher level, TAuthenticate::HasTimedOut() gives information about timeout: 0 = no timeout; 1 = timeout, no methods left; 2 = timeout, still methods to be tried. Caller should decide about an additional attempt. Timeout is disabled by default (< 0). It can be changed on-the-fly with the method TAuthenticate::SetTimeOut(to_value).

Auth.Timeout:           -1

Password dialog box is set to 0 if you do not want a dialog box to be popped-up when a password is requested. Default setting is 1.

Auth.UsePasswdDialogBox: 0

Set the following to 1 if you want full SRP authentication in PROOF (Client-to-Master and Master-to-Slave).

Proofd.SendSRPPwd:        0

Set next to 1 to use SSH authentication in PROOF servers (Master-to-Slave or Slaves-to-DataServers). This is switched off by default because credentials forwarding for SSH is not controlled by the system; however the user may have other ways to guarantee it, so it may want to switch it on.

ProofServ.UseSSH:       0

Default login name (if not defined it is taken from $(HOME)).

UsrPwd.Login:           qwerty
SRP.Login:              qwerty
Krb5.Login:             qwerty@LOCAL.DOM.AIN
Globus.Login:           cd:~/.globus cf:usercert.pem  kf:userkey.pem
SSH.Login:              qwerty
UidGid.Login:           qwerty

To be prompted for login information.

UsrPwd.LoginPrompt:     yes
SRP.LoginPrompt:        yes
Krb5.LoginPrompt:       yes
Globus.LoginPrompt:     yes
SSH.LoginPrompt:        yes
UidGid.LoginPrompt:     yes

To reuse established security context.

UsrPwd.ReUse:           yes
SRP.ReUse:              no
Krb5.ReUse:             no
Globus.ReUse:           yes
SSH.ReUse:              yes

Duration validity of the sec context for UsrPwd, SRP and SSH. Format: <hours>:<minutes> (default 24:00)

#UsrPwd.Valid:          24:00
#SRP.Valid:             24:00
#SSH.Valid:             24:00

To control password encryption for UsrPwd authentication.

UsrPwd.Crypt:             yes

Globus Miscellaneous - Globus Proxy duration: HH:MM (ex 12:15 for 12 hours and 15 min); ‘default’ for system default.

Globus.ProxyDuration:     default
#Globus.ProxyDuration:    12:15

Number of bits for the initial key.

Globus.ProxyKeyBits:      1024

Path to alternative ‘ssh’ (to override $PATH if ever needed).

SSH.ExecDir:              /usr/bin

In case of error, SSH returns 1 (or 256=0x100). To trap those errors for which one should retry, error printouts must be parsed; any substring found under the TEnv SSH.ErrorRetry triggers a retry condition; strings can be added here in the form (including double quotes):

+SSH.ErrorRetry:         "<error_string>"

This is what one usually gets if the server has reached the maximum number of sshd daemons (defined by MaxStartups in sshd_config); this is a typical case in which one should retry.

SSH.ErrorRetry:          "Connection closed by remote host"

Max number of retries for SSH in case of retry error (see above).

SSH.MaxRetry:            100

Type of key to be used for RSA encryption: 0=local; 1=SSL (default if openssl available).

RSA.KeyType:             1

In case of 'RSA.KeyType: 1’ this specifies the number of bits to be used for the Blowfish key used to encrypt the exchanged information: default - 256, minimum - 128, maximum - 15912.

SSL.BFBits:              256 Server Authentication in TServerSocket

General setting: file with server access rules

SrvAuth.DaemonRc:        /etc/root/system.daemonrc

Check of host equivalence via /etc/hosts.equiv or $HOME/.rhosts.

SrvAuth.CheckHostsEquivalence: 1

SRP: pass file (default $HOME/.srootdpass).

SrvAuth.SRPpassfile:     $HOME/.srootdpass

Globus/GSI: hostcert configuration file.

SrvAuth.HostCert:         /etc/root/hostcert.conf

Globus/GSI: gridmap file.

SrvAuth.GridMap:          /etc/grid-security/grid-mapfile

SSH: port for the sshd daemon.

SrvAuth.SshdPort:         22

Force file opening via TNetFile (TXNetFile) if a hostname is specified in the Url. By default, for local files TFile::Open() invokes directly TFile.

TFile.ForceRemote:        yes

Special cases for the TUrl parser, where the special cases are parsed in a protocol + file part, like rfio:host:/path/file.root, castor:/path/file.root or /alien/path/file.root. In case the file namespace descriptor ends with - the namespace is not a part of the filename. Extend in private .rootrc with a +Url.Special line.

Url.Special:             file: rfio: hpss: castor: gfal: dcache:
+Url.Special:            /alien/- /castor/ PROOF XRD Client Variables

Debug level (if <=0 : none, 1 : low, 2 : medium, 3 : high)

XProof.Debug:       0

Socket read timeout [in secs: default 10 secs]

XProof.ReadTimeout: 10

The following env vars are handled by TXNetFile and related classes (module netx, libNetx.so).

XNet.ConnectTimeout - maximum time to wait before server’s response on a connect [10 s]

XNet.RequestTimeout - maximum time to wait before considering a read/write failure [60 s]

XNet.ConnectDomainAllowRE - sequence of TRegexp regular expressions separated by a |. A domain is granted access to for the first connection if it matches one of these regexps. Example:


XNet.ConnectDomainDenyRE - sequence of TRegexp regular expressions separated by a |. A domain is denied access to for the first connection if it matches one of these regexps.

XNet.RedirDomainAllowRE - sequence of TRegexp regular expressions separated by a |. A domain is granted access to for a redirection if it matches one of these regexps. Example:

XNet.RedirDomainDenyRE - sequence of TRegexp regular expressions separated by a |. A domain is granted access to for a redirection if it matches one of these regexps.

XNet.MaxRedirectCount - maximum number of redirections from server [default - 255]

XNet.Debug - log verbosity level (0=nothing,1=messages of interest to the user, 2=messages of interest to the developers (includes also user messages), 3=dump of all sent/received data buffers (includes also user and developers messages). [default - 0]

XNet.ReconnectTimeout - sleep-time before going back to the load balancer (or rebouncing to the same failing host) after a read/write error [default - 10s]

XNet.StartGarbageCollectorThread - for test/development purposes. Normally nonzero (true), but as workaround for external causes someone could be interested in not having the garbage collector thread around. [experimental!]

XNet.GoAsynchronous - default is 0. When activated, XTNetFile works in async mode, allowing input buffering and unsolicited responses [experimental!]

XNet.TryConnect - Number of tries connect to a single server before giving up.

XNet.TryConnectServersList - number of connect retries to the whole server list given [default - 240]

XNet.PrintTAG - Print a particular string the developers can choose to quickly recognize the version at run time [default - 0]

Example of custom setting for the Rint application (root.exe). This overrides the default specified above for a generic application. Color 5 is yellow.

Rint.Canvas.HighLightColor:      5

30.7 Documentation to Download