Compiled program in C++ wouldn't run

Question

Dear gurus,
I am using Sun Studio Express installed in Open Solaris for x86-chip as guest running from xVM with Windows Vista as host.
As a newbie learning to compile in Open Solaris environment, I wrote a naive test script
using gedit text editor as follows:
#include <iostream>
int main() {
using namespace std;
cout<<"Hello, world."
return 0;
and saved it as greeting.cc in the folder.
Compilation is okay, but when tried to execute, it fail to run.
Attached is a log of terminal output for your kind reference:
lin@OpenSolaris:~$ CC randnorm.cc
lin@OpenSolaris:~$ ls
a.out Desktop     Documents Download Public randnorm.cc randnorm.cc~
lin@OpenSolaris:/opt$ a
bash: a: command not found
lin@OpenSolaris:/opt$ a.exe
bash: a.exe: command not found
lin@OpenSolaris:/opt$ a.out
bash: a.out: command not found
I'd be very grateful if you could kindly advise me on this
Many thanks for your precious time and advice.
Best
Lin

Answer 1

I sounds like you might be new to Unix in general.
In Unix, there is no default file extension for executable files, nor is any file extension needed. To run a command, you need to type the name of the file. For example, you could create three different executable programs called "a", "a.exe", and "a.out", and all could be in the same directory. You would run one of them by typing the full file name.
In Unix, you have an "execution path", a list of directories that are automatically searched for commands. If you don't set the path in a login script, the path does not include ".", the current directory. So even though "a.out" was in the current directory ".", "." is not on your search path, so it was not found. You could run the program by typing "./a.out" (without the quotes).
By default, Open Solaris gives you the "bash" shell as your login shell. (Other shells are available, such as sh and csh.) The command
man bashwill give you a somewhat condensed set of instructions for using bash. More generally, "man command-name" will give you a more or less brief description of "command-name".
If you have a printer installed, you can run
man -t bashto print the bash manual.
I think your next step is to get an introductory Unix and/or bash book, such as the O'Reilly books, or possibly Unix for Dummies. (I'm not calling you a dummy :-), and I strongly dislike the "for Dummies" in the titles of this book series, but many people like them.)
Books about Linux will partially apply, but there are differences between Linux and Solaris that could prove confusing when you are starting out. I recommend not using a Linux reference for Solaris.