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#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <fcntl.h>
#include <sys/stat.h>
void usage(const char *prog_name, char *filename)
{
printf("Usage: %s <data to add to %s>\n", prog_name, filename);
exit(0);
}
void fatal(char *);
void *ec_malloc(unsigned int);
int main(int argc, const char *argv[])
{
int fd;
char *buffer, *datafile;
buffer = (char *) ec_malloc(100);
datafile = (char *) ec_malloc(20);
strcpy(datafile, "/tmp/notes");
if (argc < 2)
usage(argv[0], datafile);
strcpy(buffer, argv[1]);
printf("[DEBUG] buffer @ %p: \'%s\'\n", buffer, buffer);
printf("[DEBUG] datafile @ %p: \'%s\'\n", datafile, datafile);
strncat(buffer, "\n", 1);
fd = open(datafile, O_WRONLY|O_CREAT|O_APPEND, S_IRUSR|S_IWUSR);
if (fd == -1)
fatal("in main() while opening file");
printf("[DEBUG] file descriptor is %d\n", fd);
if (write(fd, buffer, strlen(buffer)) == -1)
fatal("in main() while writing buffer to file");
if(close(fd) == -1)
fatal("in main() while closing file");
printf("note has been saved.\n");
free(buffer);
free(datafile);
return 0;
}
void fatal(char *message)
{
char error_message[100];
strcpy(error_message, "[!!] Fatal Error ");
strncat(error_message, message, 83);
perror(error_message);
exit(-1);
}
void *ec_malloc(unsigned int size)
{
void *ptr;
ptr = malloc(size);
if (ptr == NULL)
fatal("in ec_malloc() on memory allocation");
return ptr;
}
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