Reply to: An Interview with the Indians

[Sysman]

GNU bash, version 3.2.17(1)-release (powerpc-apple-darwin9.0)
Copyright (C) 2005 Free Software Foundation, Inc.

echo $$
3946

Can anyone explain that?

Ah, Thanks Dave.

ps -ax |grep 3946
3946 ttys000 0:00.07 -bash

[OrangeHopper]

GNU bash, version 3.2.17(1)-release (powerpc-apple-darwin9.0)
Copyright (C) 2005 Free Software Foundation, Inc.

echo $$
3946

Can anyone explain that?

On the Mac you get ...

echo $$
760

[Sysman]

Microsoft Windows [Version 6.0.6002]
Copyright (c) 2006 Microsoft Corporation.  All rights reserved.

c:\>echo $$
$$

??

GNU bash, version 3.2.17(1)-release (powerpc-apple-darwin9.0)
Copyright (C) 2005 Free Software Foundation, Inc.

echo $$
3946

Can anyone explain that?

[chef]

but.. but ... what about SKA? and lunch reports? and all that opinionated knowledge.. I truly hope he comes back soon and tells us his thoughts, life is just not the same without the squirrel loving ruskie around..

[cailin maith]

We'll have to wait 366 days - he's gone silent hasn't he?

[OrangeHopper]

??????

See new thread.

[chef]

that's all well and good talking about apples and indians and cars and whatnot but what we really want, nay NEED to know, is what AtW has had for lunch and what s the latest SKA news?

[zeitghost]

the ECHO command is the same between Windows and UNIX. It sends it's argument to the standard output. ( The command line usually ).

The confusion here is with the way UNIX handles variables. To define a variable and send it to the standard output in unix you use

> foo=bar
> ECHO $foo
> bar

The trick with ECHO $$ is that Unix has a number of predetermined variables, set at shell and environment level that contain specific pieces of infomation.

$ is the variable name used to identify the ID of the currently running process. So 'ECHO $$' will return the current value of $. Others include :

• $1 - $9 these variables are the positional parameters.
  
• $0 the name of the command currently being executed.
  
• $# the number of positional arguments given to this
• invocation of the shell.
  
• $? the exit status of the last command executed is
• given as a decimal string. When a command
• completes successfully, it returns the exit status
• of 0 (zero), otherwise it returns a non-zero exit
• status.
  
• $$ the process number of this shell - useful for
• including in filenames, to make them unique.
  
• $! the process id of the last command run in
• the background.
  
• $- the current options supplied to this invocation
• of the shell.
  
• $* a string containing all the arguments to the
• shell, starting at $1.
  
• $@ same as above, except when quoted.

It's all further complicated by the distinction between SHELL and ENVIRONMENT variables ( SHELL variables only apply to the current shell, ENVIRONMENT variables apply to all Shells ) and the fact that a single user can run multiple shells all with different variables defined, at the same time, and switch between them at will.

I thank you.

Your turn now ZG. What is a NIXIE tube and why on earth would anyone eant to use them in a watch?

A nixie tube is a long obsolete display technology invented in the 1950s.

It uses neon gas at low pressure in a thing that looks like a valve to display the numbers 0 to 9.

These are now rather popular for making clock displays. Probably because they're expensive.

As to why you'd want two in your wrist watch, I'm afraid it's beyond me.

Must take a lot of batteries to keep it going.

[scotspine]

ah, a mac person. how quaint

how was the hook-dipping this year oh?

??????

[TheFaQQer]

I went and looked it up on Wikipedia. Was most dissapointed by the link to a "Split Flap Display".

[DaveB]

Don't know what one is, but the obvious two answers as to why use them as a watch are answered in the video:

1) Because you're a big fat beardy geek.

2) Because you like scaring Americans on planes who think you are going to blow it up.

I went and looked it up on Wikipedia. Was most dissapointed by the link to a "Split Flap Display".

[TheFaQQer]

What is a NIXIE tube and why on earth would anyone eant to use them in a watch?

Don't know what one is, but the obvious two answers as to why use them as a watch are answered in the video:

1) Because you're a big fat beardy geek.

2) Because you like scaring Americans on planes who think you are going to blow it up.

[DaveB]

WHS.

Please be more explicit for the benefit of the Lizardly community.

Thank you in anticipation.

the ECHO command is the same between Windows and UNIX. It sends it's argument to the standard output. ( The command line usually ).

The confusion here is with the way UNIX handles variables. To define a variable and send it to the standard output in unix you use

> foo=bar
> ECHO $foo
> bar

The trick with ECHO $$ is that Unix has a number of predetermined variables, set at shell and environment level that contain specific pieces of infomation.

$ is the variable name used to identify the ID of the currently running process. So 'ECHO $$' will return the current value of $. Others include :

• $1 - $9 these variables are the positional parameters.
  
• $0 the name of the command currently being executed.
  
• $# the number of positional arguments given to this
• invocation of the shell.
  
• $? the exit status of the last command executed is
• given as a decimal string. When a command
• completes successfully, it returns the exit status
• of 0 (zero), otherwise it returns a non-zero exit
• status.
  
• $$ the process number of this shell - useful for
• including in filenames, to make them unique.
  
• $! the process id of the last command run in
• the background.
  
• $- the current options supplied to this invocation
• of the shell.
  
• $* a string containing all the arguments to the
• shell, starting at $1.
  
• $@ same as above, except when quoted.

It's all further complicated by the distinction between SHELL and ENVIRONMENT variables ( SHELL variables only apply to the current shell, ENVIRONMENT variables apply to all Shells ) and the fact that a single user can run multiple shells all with different variables defined, at the same time, and switch between them at will.

Your turn now ZG. What is a NIXIE tube and why on earth would anyone eant to use them in a watch?

[TheFaQQer]

We're just waiting for ATW to join in and enlighten us all on where we've gone wrong. Then the thread will be complete and it eventually with fall of the precipice of page 1. Probably forever.

AtW

[snaw]

Is this what you call a double-hijack, the thread has been hijacked by the second hand car sellers and now by the great Apple debate !

We're just waiting for ATW to join in and enlighten us all on where we've gone wrong. Then the thread will be complete and it eventually with fall of the precipice of page 1. Probably forever.