C in Linux. The program only read the first line and then stop

Linh · 07-03-2003, 03:38 PM

The program only read the first line and then stop

==============================
# Samba SMB password file
public:501:85DBEE24101CEFF8AAD3B435B51404EE

B51013B2730E1F16DF6DB7C3A73AD60:[U ]:LCT-3AB622A2:
admin:501:2B251B4003C6F043CA53DE06F7962527:C2D7C320A09B649A91AEC96D4CC32662:[UX ]:LCT-3E21AEC3:

==============================
root:~# ./getdata2
single_char = #
single_char =
single_char = S
single_char = a
single_char = m
single_char = b
single_char = a
single_char =
single_char = S
single_char = M
single_char = B
single_char =
single_char = p
single_char = a
single_char = s
single_char = s
single_char = w
single_char = o
single_char = r
single_char = d
single_char =
single_char = f
single_char = i
single_char = l
single_char = e
single_char =

=================================
#include <stdio.h>

read_smbpasswd_file()
{
FILE *file_pointer, *fopen();
char user_name[32];
char single_char;
int i = 0;

memset(user_name, '\0', 32);
file_pointer = fopen("/etc/samba/smbpasswd", "r");

single_char = getc(file_pointer);
while(!feof(file_pointer))
{
if (single_char != ':')
{
user_name[i] = single_char;
printf ("single_char = %c\n", single_char);
i++;
single_char = getc(file_pointer);
}
else
printf ("user_name[] = %s", user_name);
}
fclose (file_pointer);
}

/******************************************/

main()
{
read_smbpasswd_file();
}

TheLinuxDuck · 07-03-2003, 04:31 PM

Code:

#include <stdio.h>

int main(void)
{
  FILE *in;
  char buffer[255];
  int n;

  if((in = fopen("smbpasswd","r")) == NULL) {
    perror("Couldn't open file");
    return 1;
  }

  fgets(buffer, 255, in);
  n = strlen(buffer) - 1;

  if(n < 1)
    printf("nothing read from file\n");
  else {
    if(buffer[n] == '\n') buffer[n] = '\0';
    printf("%s\n", buffer);
  }
 
  fclose(in);
  return 0;
}

A bit more efficient, and also checks for errors. (=

Linh · 07-03-2003, 04:40 PM

I ran the new code but the last line is printed twice.

===========================
root:~# ./getdata3

# Samba SMB password file
public:501:85DBEE24101CEFF8AAD3B435B51404EE

B51013B2730E1F16DF6DB7C3A73AD60:[U ]:LCT-3AB622A2:
user_name[] = public
admin:501:2B251B4003C6F043CA53DE06F7962527:C2D7C320A09B649A91AEC96D4CC32662:[UX ]:LCT-3E21AEC3:
user_name[] = admin

The last line below was printed twice

admin:501:2B251B4003C6F043CA53DE06F7962527:C2D7C320A09B649A91AEC96D4CC32662:[UX ]:LCT-3E21AEC3:
user_name[] = admin

===========================

int main(void)
{
FILE *in;
char buffer[255];
char user_name[32];
int n;
int i = 0;

if((in = fopen("/etc/samba/smbpasswd","r")) == NULL)
{
perror("Couldn't open file");
return 1;
}

while(!feof(in))

{
fgets(buffer, 255, in);
n = strlen(buffer) - 1;

if(n == 0)
printf("nothing read from file\n");
else
{
if(buffer[n] == '\n')
buffer[n] = '\0';
printf("%s\n", buffer);
}

for (i = 0; i <= 254; i++)
if (buffer[i] != ':')
user_name [i] = buffer[i];
else
{
user_name [i] = '\0';
printf ("user_name[] = %s\n", user_name);
break;
}
}

fclose(in);
return 0;
}