Faili nimi käsureaargumendina

Järgnev näiteprogramm võtab käsurealt faili nime mida lugeda.

Sisendfail peaks koosnema täisarvulistest numbritest, eraldatud tühiku või reavahetusega. Sisendfaili lugemine katkestatakse mittenumbrilise väärtuse leidmisel või faili lõppu jõudes.

/**
 * File:        file_args.c
 * Author:      Risto Heinsar
 * Created:     15.08.2022
 *
 * Description: Example on accepting the name of the input file 
 *              as the command line argument. Argument must be provided
 *              when using the program. 
 *              Input file should contain integers only.
 *
 * Usage:       ./program_name input_file_name
 */
#include <stdio.h>
#include <stdlib.h>

#define ARG_COUNT 2
#define ARG_POS_EXEC 0
#define ARG_POS_FILENAME 1

void DisplayNumsInFile(FILE *fp);

int main(int argc, char *argv[])
{
	// Check that argument was provided
	if (argc != ARG_COUNT)
	{
		printf("Usage %s file.\n", argv[ARG_POS_EXEC]);
		return EXIT_FAILURE;
	}
	
	// Open the file
	FILE *fp = fopen(argv[ARG_POS_FILENAME], "r");
	if (fp == NULL)
	{
		printf("Error opening file \"%s\".\n", argv[ARG_POS_FILENAME]);
		return EXIT_FAILURE;
	}
	
	DisplayNumsInFile(fp);
	
	// Clean up
	fclose(fp);
	
	return EXIT_SUCCESS;
}

void DisplayNumsInFile(FILE *fp)
{
	int temp;
	int i = 1;
	
	// Loop through the file
	while (fscanf(fp, "%d", &temp) == 1)
	{
		printf("%d. %d\n", i, temp);
	}
	printf("End of file or unexpected format reached!\n");
}

/**

* File: file_args.c

* Author: Risto Heinsar

* Created: 15.08.2022

* Description: Example on accepting the name of the input file

* as the command line argument. Argument must be provided

* when using the program.

* Input file should contain integers only.

* Usage: ./program_name input_file_name

#include <stdio.h>

#include <stdlib.h>

#define ARG_COUNT 2

#define ARG_POS_EXEC 0

#define ARG_POS_FILENAME 1

void DisplayNumsInFile(FILE *fp);

int main(int argc, char *argv[])

{

// Check that argument was provided

if (argc != ARG_COUNT)

{

printf("Usage %s file.\n", argv[ARG_POS_EXEC]);

return EXIT_FAILURE;

}

// Open the file

FILE *fp = fopen(argv[ARG_POS_FILENAME], "r");

if (fp == NULL)

{

printf("Error opening file \"%s\".\n", argv[ARG_POS_FILENAME]);

return EXIT_FAILURE;

}

DisplayNumsInFile(fp);

// Clean up

fclose(fp);

return EXIT_SUCCESS;

}

void DisplayNumsInFile(FILE *fp)

{

int temp;

int i = 1;

// Loop through the file

while (fscanf(fp, "%d", &temp) == 1)

{

printf("%d. %d\n", i, temp);

}

printf("End of file or unexpected format reached!\n");

}