Printing out extra numbers? (C) - c

Question

Hello I'm writing a program right now that read in values from files.
It reads in the values as strings by fgets
and then I wanted to change one of the strings into integers:
#include <stdio.h>
#include <string.h>
#include <stdbool.h>
#include <stdlib.h>
#define FILSIZE 1024
typedef struct _node
{
unsigned int uid;
char *uname;
struct _node *next;
} *node;
int main(int argc, char* argv[])
{
FILE *pFile; // pointer file
char currentLine[FILSIZE];
bool isListEmpty = true;
node firstNode = NULL;
printf( "\n\nargc: %d\nargv[0]: %s\nargv[1]: %s\n\n", argc, argv[0], argv[1] );
if(argc == 1)
{
pFile = stdin;
}
else if (argc == 2)
{
char buffer [50];
sprintf(buffer, "%s.txt" ,argv[1]);
printf("%s", buffer);
pFile = fopen(buffer, "r");
}
if(pFile == NULL )
{
printf("Not working");
exit(0);
}
int i=1;
int nameCounter = 1;
int colonCounter=0;
while(!feof( pFile ) && fgets(currentLine, sizeof(currentLine), pFile))
{
unsigned int nameLength;
unsigned int tempuid;
unsigned int idstorlek;
node firstNode = malloc(sizeof(struct _node));
char *temporaryString;
temporaryString = strtok(currentLine, ":");
colonCounter=colonCounter+1;
//printf(" fungera pls");
printf(" %d Namnordning %s \n", nameCounter, temporaryString);
nameLength = strlen(temporaryString);
firstNode->uname = malloc((nameLength+1) * sizeof(char));
strcpy(firstNode->uname, temporaryString);
printf("NAMNET: %s \n", temporaryString);
while(temporaryString != NULL)
{
printf(" %s \n", temporaryString);
if(colonCounter == 3)
{
int tempuid=atoi(temporaryString);
// idstorlek = sizeof(tempuid);
// firstNode->uid = malloc(4);
printf(" IDN: %d \n", tempuid);
firstNode->uid = tempuid;
printf("firstNodeid %d", firstNode->uid);
}
temporaryString = strtok(NULL, ":");
colonCounter=colonCounter+1;
}
if(colonCounter == 6)
{
// printf("FUNGERAR ID: %d NAMN %s \n", tempuid, firstNode->uname);
}
printf("%d Row is done \n", i);
i=i+1;
nameCounter = nameCounter+1;
colonCounter = 0;
}
}
But when I write it out I get:
1 Namnordning mr
NAMNET: mr
mr
x
1171
IDN: 1171
firstNodeid 1171 1101
Mikael R�nnar
/Home/staff/mr
/usr/local/bin/tcsh
1 Row is done
2 Namnordning axelsson
NAMNET: axelsson
axelsson
x
12856
IDN: 12856
firstNodeid 12856 1101
Bj�rn Axelsson
/Home/staff/axelsson
/usr/local/bin/tcsh
2 Row is done
3 Namnordning gabriel
NAMNET: gabriel
gabriel
x
16928
IDN: 16928
firstNodeid 16928 1101
Gabriel Jonsson
/Home/staff/gabriel
/usr/local/bin/tcsh
3 Row is done
4 Namnordning set
NAMNET: set
set
x
12037
IDN: 12037
firstNodeid 12037 1101
Set Norman
/Home/staff/set
/usr/local/bin/tcsh
4 Row is done
5 Namnordning dahlin
NAMNET: dahlin
dahlin
x
12928
IDN: 12928
firstNodeid 12928 1101
Fredrik Dahlin
/Home/staff/dahlin
/usr/local/bin/tcsh
5 Row is done
6 Namnordning fahlgren
NAMNET: fahlgren
fahlgren
x
17847
IDN: 17847
firstNodeid 17847 1101
Daniel Fahlgren
/Home/staff/fahlgren
/usr/local/bin/tcsh
6 Row is done
Why do I get 1101 too there?
The other tempuid part only gives me the correct id.
Am I not locating the memory right? (I been trying to and it only gives me weird errors, with the idsize part).

Answer 1

It's because you're not flushing the print buffer after you call
printf("firstNodeid %d", firstNode->uid);
printf stores a buffer of characters rather than writing a string to stdout as soon as it gets them to avoid the overhead of calling the lower-level write function too often.
Instead calling:
printf("firstNodeid %d\n", firstNode->uid);
Should fix your problem because "\n" will add a newline to the string, and flush the output.
Edit: You should also be careful with types. You're defining tempuid as an int:
int tempuid=atoi(temporaryString);
// idstorlek = sizeof(tempuid);
// firstNode->uid = malloc(4);
printf(" IDN: %d \n", tempuid);
firstNode->uid = tempuid;
printf("firstNodeid %d", firstNode->uid);
But defining it as an unsigned int in your node struct.

Answer 2

Normally you should post a small, complete example demonstrating the behavior (you'll often find the bug yourself when doing this).
But it turns out that you have posted enough information to give a pretty clear indicator: your code is not printing out an extra number. Instead, it's merely failing to print a newline; the next piece of code that does output will start writing on the same line.