Kenwood HP 9000 manual Compiling Programs on HP-UX An Example

What Happens When You Compile and Link a Program

Compiling Programs on HP-UX: An Example

Compiling Programs on HP-UX: An Example

To create an executable program, you compile a source file containing a main program. For example, to compile an ANSI C program named sumnum.c, shown below, use this command (-Aasays to compile in ANSI mode):

$ cc -Aa sumnum.c

The compiler displays status, warning, and error messages to standard error output (stderr). If no errors occur, the compiler creates an executable file named a.out in the current working directory. If your PATH environment variable includes the current working directory, you can run a.out as follows:

$ a.out

Enter a number: 4

Sum 1 to 4: 10

The process is essentially the same for all HP-UX compilers. For instance, to compile and run a similar FORTRAN program named sumnum.f:

$ f77 sumnum.f	Compile and link sumnum.f.
...	The compiler displays any messages here.
$ a.out	Run the program.
...	Output from the program is displayed here.

Program source can also be divided among separate files. For example, sumnum.c could be divided into two files: main.c, containing the main program, and func.c, containing the function sum_n. The command for compiling the two together is:

$ cc -Aa main.c func.c main.c:

func.c:

Notice that cc displays the name of each source file it compiles. This way, if errors occur, you know where they occur.

#include	<stdio.h>	/* contains			standard I/O defs */
int	sum_n( int n )	/* sum		numbers from n to 1		*/
{
int	sum = 0;	/*	running		total; initially 0 */
for (;	n >= 1; n--)	/*	sum	from n to 1		*/

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