macOS Using C programming language book but i'm stuck

[thedon1]

I'm using the C programming language book by Keringhan and Ritchie.

I'm on page 20, 1.5.4, section on word counting.

It introduces a symbol which it says means "or."

It looks like 2 vertical brackets, one stacked on another.

How do i write this on my keyboard?

Any other considerations i need to make?

 

[lee1210]

This is two pipe characters. |, I don't have a real keyboard and type by touch, but it's near the return key. Might be the shifted character on a key.

-Lee

Edit: Shifted backslash, \. looks like it's just above return on the US layout. Might vary slightly on a laptop. It might be shown "broken" half way up. Sorry for the US-centric reply; if you use another layout, say which.

 

[Catfish_Man]

It's shift+\

 

[thedon1]

Nice one guys, it was broken in the book so it threw me off.

Thanks

 

[chown33]

Nice one guys, it was broken in the book so it threw me off.

Its appearance varies:
http://en.wikipedia.org/wiki/Vertical_bar

 

[thedon1]

One more question about this chapter.

I have written the code for the examples on word counting, line counting ad arrays in chapter one but how do i get the program to actually count something?

I open the console and go to build and run just like the other examples but i don't know what input the code is looking for.

Are these not practical examples or am i missing something?

 

[lloyddean]

Select "Edit Active Executable" at the bottom of the "Project" menu will bring up an "Info" window.

Select the second view-tab titled "Arguments".

Click the "+" button at the bottom of the "Info" window to add parameters that wold be passed on the command line.

 

[lee1210]

I think this example reads from stdin until it hits EOF. You can enter text at the console, then enter ctrl+d to end input. This is one of the reasons I think an IDE can hinder learning, having to figure out the intricacies of the IDE while trying to figure out the language.

-Lee

 

[thedon1]

I think this example reads from stdin until it hits EOF. You can enter text at the console, then enter ctrl+d to end input. This is one of the reasons I think an IDE can hinder learning, having to figure out the intricacies of the IDE while trying to figure out the language.

-Lee

Perfect, that worked, thanks

 

[chown33]

You can also copy and paste text into Xcode's console window. You still have to type control-D manually.

If this seems like a useless way to run programs, it's because the original code is intended for use on a command-line, where you can redirect input and output to any file with simple notations. If the program's name is 'woc', examples might be:

woc <anyfile.txt
ifconfig | woc
ftpCount=`woc </etc/ftpusers`

The first counts the words in anyfile.txt. The second counts the words in the output of the 'ifconfig' command. The third counts words in /etc/ftpusers and assigns that count to the shell variable ftpCount.

 

[thedon1]

You can also copy and paste text into Xcode's console window. You still have to type control-D manually.

If this seems like a useless way to run programs, it's because the original code is intended for use on a command-line, where you can redirect input and output to any file with simple notations. If the program's name is 'woc', examples might be:

woc <anyfile.txt
ifconfig | woc
ftpCount=`woc </etc/ftpusers`

The first counts the words in anyfile.txt. The second counts the words in the output of the 'ifconfig' command. The third counts words in /etc/ftpusers and assigns that count to the shell variable ftpCount.

i'm assuming the .txt file is in the same folder as the program right?

 

[chown33]

i'm assuming the .txt file is in the same folder as the program right?

Or 'woc' is in a directory listed in PATH, which is a list of directories to search for commands.

The plain unadorned pathname "anypath.txt" always refers to a file in the current working directory. It doesn't start with "/", so that means it's a relative pathname, not an absolute pathname. And it contains no other /-separated names, so it's not referring to any other directories.
http://en.wikipedia.org/wiki/Working_directory
http://en.wikipedia.org/wiki/Path_(computing)


As far as I know, you can't use any of the examples I gave in Xcode. Its console window is not a command-line shell.

Your Executable for the Xcode project lets you control the working directory when you run the program. Double click the Executable and you'll see a tab that lets you change the environment.