Installing g95 on OS X

Hi, I'm attempting to install g95 on OS X (Jaguar), but being a
complete Darwin newbie, I really don't understand the instructions
that go with it. What does it mean by saying "G95 and friends expect
to live under /tmp/g95"? Does that mean I have to move files around
into some new directory that I've created? Can I do this in the GUI?
I'm actually quite scared of poking around in Darwin because I was
once told that I could completely wreck it if I didn't know what I was
doing...

I'd be really grateful if anyone can help me out here. Thanks!

Nat

sebire@hotmail.com (Nat) writes:

I don't know anything about the particular g95-related question you asked,
but...

> I'm actually quite scared of poking around in Darwin because I was
> once told that I could completely wreck it if I didn't know what I was
> doing...

Somebody appears to have oversensitized you to this.  While it is true,
the same thing is true of pretty much every operating system out there.

Proofs by demonstration exist.  I have first-hand evidence of this
on both Windows-based and Unix systems.   :-( It happens that I haven't
completely trashed any of my Macs, but I certainly know ways that it
could happen. Probably the only thing that has "saved" me is that I've
only been using them for about a year and a half I think it has been.
I have trashed some apps, but not the whole system...yet.

I've trashed my Windows boxes several times.  Heck, it has been argued
(with some merit) that one should rebuild a Windows box from scratch
about every other year anyway in order to remove "cruft" that will
have accumulated.

Unix boxes tend to be harder in that it tends to take symin
permission for most ways of trashing them. But I symin several.  :-(
The usual (and very good) advice is to keep separate accounts for
daily use and for symin stuff.

OS X is a Unix box, well at least for current purposes, and the same
caveat applies. The only way in which I might say it was particularly
easy to wreck it is that most people will set themselves up so that
the account they use for daily use has symin privileges.  Doesn't
have to be that way, but that's how most systems are (because it's
what happens by default if you don't set it up otherwise). But your
typical Windows box has the same kind of setup. Most other Unix boxes
aren't set up like this... but the added danger is when you *AREN'T*
intentionally using the system privileges. As soon as you are intentionally
doing symin work, you have the same kinds of potential problems.

If you are really worried, it would be a lot more constructive to
make 2 accounts - one for daily use and one for symin - than to
be afraid of ever touching the machine.  I did that for a while...
but got lazy.

In any case, have backups.  No matter what.  No matter what OS or
how you use it.  I've sympathized with no end of people who lost
huge amounts of work because they thought they didn't need backups
(or most often, just didn't think about it at all). Usually sympathy
is about all I can offer.  Yep, some of them were on Macs.

It is probably a corollary of Murphy's law that the only people who
don't need backups are the people who do them... but it is worth doing
the backups just to make sure that you won't need them.  :-)

If you are going to be quite a scared of touching the system as you
describe, then I shouldn't tell you that I've trashed a Windows/Linux
(dual-boot) system by just touching the keyboard without even
depressing a key.  :-( Darned static electricity.  Fried the keyboard
controller, which meant a new motherboard.

--
Richard Maine                       |  Good judgment comes from experience;
email: my first.last at org.domain  |  experience comes from bad judgment.
org: nasa, domain: gov              |        -- Mark Twain

On 18 Oct 2004 15:05:34 -0700, Nat wrote:
> Hi, I'm attempting to install g95 on OS X (Jaguar), but being a
> complete Darwin newbie, I really don't understand the instructions
> that go with it. What does it mean by saying "G95 and friends expect
> to live under /tmp/g95"? Does that mean I have to move files around
> into some new directory that I've created? Can I do this in the GUI?
> I'm actually quite scared of poking around in Darwin because I was
> once told that I could completely wreck it if I didn't know what I was
> doing...

> I'd be really grateful if anyone can help me out here. Thanks!

Do you really need g95 rather than gfortran?  Both are f95 compilers, but
gfortran is easier to install on the Mac.  If you have fink installed, all y
ou
need to do is type

sudo fink install gfortran

and let it build.  See <http://fink.sourceforge.net> if you need to install
fink.  This assumes that you have Apple's Developer Tools (known as Xcode in
Panther) already installed.  You may be able to install a prebuilt binary us
ing
the apt-get command (that's not necessarily available for all fink products,
and I haven't tried it).

If you really need g95, then you need to know that there are some standard
locations that are recognized by all versions of Unix and Linux (including
Darwin):

/tmp		Temporaries.  It's ok to place files here, but you
should understand that they may be deleted the next
time you reboot.  Why they would insist on having a
symbolic link in /tmp is beyond me.

/usr/local	Traditionally a place to install things that are not
provided as part of the operating system.  For example,
you could create a directory /usr/local/g95-install
by untaring the distribution file.

To install in /usr/local you will need to use the 'sudo' command, which give
s
you root access for a single command.  You will probably also want to create
 a
/usr/local/bin directory if you don't have one yet, and place a symbolic lin
k
g95 in that directory as described in the INSTALL file.  You also need to ma
ke
sure /usr/local/bin is in your PATH, where PATH is a shell variable that
controls where the shell looks for executable programs that you call from th
e
command line.

If the preceding paragraph looks like gibberish to you, you may want to
consider installing fink and using gfortran instead, since more of the proce
ss
is automated when you go that route.

--
Dave Seaman
Judge Yohn's mistakes revealed in Mumia Abu-Jamal ruling.
<http://www.commoncouragepress.com/i...book&bookid=228>

>
>
> On 18 Oct 2004 15:05:34 -0700, Nat wrote: 
>

To get the g95 binary working do the following:

1) Download g95-powerpc-osx.tgz and put it in /tmp

2) type: su

in a shell, it will ask you for the admin password.. type it in.

3) type: cd /tmp

4) type: tar -zxf g95-powerpc-osx.tgz

5) type: ln -s /tmp/g95-install/bin/powerpc-apple-darwin6.8-g95
/usr/local/bin/g95

all this in one line.  It makes a link from /usr/local/bin/g95 to the
compiler binary in /tmp/ so you can just type g95 to compile something.

5) type:  exit


6) type:  g95 -c myprog.f90

where myprog.f90 is some simple program (make sure you are in the
directory where the program lives).  If it produces an a.out file you are
golden.  If it doesn't let me know and it means that /usr/local/bin isn't
in your path... if that is the case which I doubt e-mail again and I'll
give you directions (/usr/local/bin is a pretty standard dir for a user
account on *NIX machines and should be in your path by default).

The reason why you should untar the file in /tmp is that the compiler
thinks all its important libraries are there so it can link them at
compile time.  If you don't put it in /tmp you will have to tell the
compiler where they are using environmental variables.. so my suggestion
is to simply use /tmp... when the compiler is complete I'm sure a better
directory will be chosen.

Cheers,
Jason

On Tue, 19 Oct 2004 00:10:25 GMT, Jason Nielsen wrote:

 


> To get the g95 binary working do the following:

> 1) Download g95-powerpc-osx.tgz and put it in /tmp

> 2) type: su

> in a shell, it will ask you for the admin password.. type it in.

That won't work unless you have gone to the trouble of enabling root
logins, a procedure that is definitely not recommended on the Mac.  For
one thing, it's rather difficult to undo, once done.

Instead of 'su' you should use a command like

sudo bash

where you may substitute your favorite shell for 'bash', if desired.  You
will be asked for your account password.  You must be running under an
account that has admin privileges for this to work.

From here on until you type 'exit' you will see '#' as your prompt, which
is a reminder that you are running with root privileges and therefore you
should carefully verify each command you type before you press <return>.

> 3) type: cd /tmp

> 4) type: tar -zxf g95-powerpc-osx.tgz

This is not quite what the INSTALL file recommends.  I suggest using the
following instead:

3) cd /usr/local
4) tar -zxf /tmp/g95-powerpc-osx.tgz

and then type the following (this is between steps 4 and 5):

ln -s /usr/local/g95-install /tmp/g95

> 5) type: ln -s /tmp/g95-install/bin/powerpc-apple-darwin6.8-g95 /usr/local/bin/g95


> all this in one line.  It makes a link from /usr/local/bin/g95 to the
> compiler binary in /tmp/ so you can just type g95 to compile something.

First you should make sure the directory /usr/local/bin exists.  It
doesn't on a stock Macintosh:

mkdir -p /usr/local/bin

Next, you should modify the command 5) to specify a path beginning with
/usr/local in place of /tmp:

5) ln -s /usr/local/g95-install/bin/powerpc-apple-darwin6.8-g95 /usr/local/b
in/g95

That's supposed to be all on one line.

> 5) type:  exit

After this you are no longer running with root privileges.


> 6) type:  g95 -c myprog.f90

Assuming you have a fortran program in the file myprog.f90 in your
current directory.  If you see a response like "g95: command not found"
at this point, it means you need to add /usr/local/bin to your PATH.  The
exact method for doing that depends on your shell.  If you are using
bash, you can add the line

export PATH=/usr/local/bin:$PATH

to the file .bash_profile in your home directory (or create a new file by
that name if it doesn't exist).  From that point on, each new Terminal
window that you open will have your PATH initialized so that g95 can be
found.

> where myprog.f90 is some simple program (make sure you are in the
> directory where the program lives).  If it produces an a.out file you are
> golden.  If it doesn't let me know and it means that /usr/local/bin isn't
> in your path... if that is the case which I doubt e-mail again and I'll
> give you directions (/usr/local/bin is a pretty standard dir for a user
> account on *NIX machines and should be in your path by default).

> The reason why you should untar the file in /tmp is that the compiler
> thinks all its important libraries are there so it can link them at
> compile time.  If you don't put it in /tmp you will have to tell the
> compiler where they are using environmental variables.. so my suggestion
> is to simply use /tmp... when the compiler is complete I'm sure a better
> directory will be chosen.

I don't see how you can count on /tmp/g95-install staying put after the
next reboot.  I installed in /usr/local/g95-install and then placed a
symbolic link in /tmp, as described in the INSTALL file.  It works fine.


--
Dave Seaman
Judge Yohn's mistakes revealed in Mumia Abu-Jamal ruling.
<http://www.commoncouragepress.com/i...book&bookid=228>

Dave Seaman wrote:

> On 18 Oct 2004 15:05:34 -0700, Nat wrote: 
> 
>
> Do you really need g95 rather than gfortran?  Both are f95 compilers, but
> gfortran is easier to install on the Mac.  If you have fink installed, all
> you need to do is type

g95 is far more complete than gfortran.

sebire@hotmail.com (Nat) writes:

| Hi, I'm attempting to install g95 on OS X (Jaguar), but being a
| complete Darwin newbie, I really don't understand the instructions
| that go with it. What does it mean by saying "G95 and friends expect
| to live under /tmp/g95"? Does that mean I have to move files around
| into some new directory that I've created? Can I do this in the GUI?
| I'm actually quite scared of poking around in Darwin because I was
| once told that I could completely wreck it if I didn't know what I was
| doing...

no it means you can have the actual g95 files anywhere, but that you
need to make a symbolic link from /tmp/g95 to that directory.

since everyone are allowed to write to /tmp, you can install g95
without needing to be the system administrator, root or whatever it is
called in the OS X world.

so the quickest way to install g95 are

1) open the terminal application
2) download g95 and install in current directory with this command
line:

wget -O - http://www.g95.org/g95-powerpc-osx.tgz | tar xvfz -

3) ln -s $PWD/g95-install /tmp/g95

finally to make an alias for the compiler in the current directory

4) ln -s /tmp/g95/bin/i686-pc-linux-gnu-g95 ./g95

you may now invoke g95 with
./g95

Helge

Dave Seaman <dseaman@no.such.host> writes:

| Files in /tmp are automatically cleaned out at boot time, as is standard
| practice on Unix boxes.  The reason it's called "tmp" is to serve as
| a

so what. most programs need some initialization of the environment, in
g95's case the only thing you need to make it work all the time is to
set a symlink to the install directory. this can trivially be done in
.bashrc or similar init script. the point is that you can install g95
without having to fiddle around as the sym...

Helge

> Files in /tmp are automatically cleaned out at boot time, as is standard
> practice on Unix boxes.  The reason it's called "tmp" is to serve as a
> warning that everything you put there is temporary.  The code for the
> cleanup on the Mac is in the file /etc/rc.cleanup.  Keep in mind that
> /tmp on a Macintosh is a symbolic link to /private/tmp:
>

This certainly isn't true at least not on my FreeBSD box (adding
clear_tmp_enable="YES" to rc.conf will do the trick) or my Linux boxes. I
use /tmp all the time to dump cruft that I'm not sure I want to delete.
That Mac uses /etc/rc.cleanup to remove stuff in /tmp does not make
deleting the contents of /tmp standard.  Granted if you are using a long
running server it might be good practice to run a cron job once a month to
clean out /tmp but that is a different matter!  So the instructions I gave
in fact work just fine on the *NIX boxes I have... none of which is a
Mac.. and for that I agree my instructions were a bit off ... just trying
to help.

Cheers,
Jason

On Tue, 19 Oct 2004 06:40:50 GMT, Jason Nielsen wrote:
 

> This certainly isn't true at least not on my FreeBSD box (adding
> clear_tmp_enable="YES" to rc.conf will do the trick) or my Linux boxes. I
> use /tmp all the time to dump cruft that I'm not sure I want to delete.
> That Mac uses /etc/rc.cleanup to remove stuff in /tmp does not make
> deleting the contents of /tmp standard.  Granted if you are using a long
> running server it might be good practice to run a cron job once a month to
> clean out /tmp but that is a different matter!  So the instructions I gave
> in fact work just fine on the *NIX boxes I have... none of which is a
> Mac.. and for that I agree my instructions were a bit off ... just trying
> to help.

Most of the Unix/Linux boxes that I deal with are running the Portable
Batch Server (PBS) for scheduling long jobs, and on those machines it is
standard practice to clean out /tmp each time a job finishes -- not just
at boot time.  Regardless of the exact policy in effect, it is sheer
madness to consider the contents of /tmp to be anything other than
temporary.

If you want to keep it, put it in /usr/local, unless your local policy
designates a different directory for that purpose.  A permanent
directory, that is.


--
Dave Seaman
Judge Yohn's mistakes revealed in Mumia Abu-Jamal ruling.
<http://www.commoncouragepress.com/i...book&bookid=228>