The file that I am trying to read has the following contents:

192.168.1.1
48111
test.out
100
25

I am trying to use fscanf to read it line by line and storing each line in a variable. This works if I just have a couple of int variables, but it does not work for the above which also has an IP address and a file name. I tried saving the IP as a string but it just outputs garbage. Any suggestions?

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Dont use fscanf use fread .
Read the input into a char buffer . Then use string processing to extract the information you need

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fscanf is a perfectly fine function to use for a configuration file with an absolute fixed format. I use it all the time. Wonderful function.

Here is an example which could be very relevant to you. This assumes linux. In windows, use the CR/LF combination.

This is the …

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Is the format of the input file pre defined or can it change
If the input file format is not fixed then this is a hard problem

Is the format of the input file pre defined or can it change
If the input file format is not fixed then this is a hard problem

The format is fixed and pre-defined. I just need to store the data in each line in different variables.

Dont use fscanf use fread .
Read the input into a char buffer . Then use string processing to extract the information you need

fscanf is a perfectly fine function to use for a configuration file with an absolute fixed format. I use it all the time. Wonderful function.

Here is an example which could be very relevant to you. This assumes linux. In windows, use the CR/LF combination.

This is the data structure.

typedef struct {
  char IP[16];
  int  Port;
  char FileName[255];
  int  Min, Max;
} DataStructure;

This is the code which performs the import. fscanf used properly makes the import extremely painless.

DataStructure Data;
FILE *f = fopen("connect.conf","r");

if (fscanf(f, "%s\n%d\n%s\n%d\n%d", Data.IP, &Data.Port, Data.FileName, &Data.Max, &Data.Min)!=5) {
  fprintf(stderr,"File not in correct format");
  return -1;
}

>> If the input file format is not fixed then this is a hard problem

Nothing is hard in C. If the file was not a fixed format, you just add a loop, int and switch.

wow thanks; that worked perfectly.

fscanf is a perfectly fine function to use for a configuration file with an absolute fixed format. I use it all the time. Wonderful function.

Here is an example which could be very relevant to you. This assumes linux. In windows, use the CR/LF combination.

This is the data structure.

typedef struct {
  char IP[16];
  int  Port;
  char FileName[255];
  int  Min, Max;
} DataStructure;

This is the code which performs the import. fscanf used properly makes the import extremely painless.

DataStructure Data;
FILE *f = fopen("connect.conf","r");

if (fscanf(f, "%s\n%d\n%s\n%d\n%d", Data.IP, &Data.Port, Data.FileName, &Data.Max, &Data.Min)!=5) {
  fprintf(stderr,"File not in correct format");
  return -1;
}

>> If the input file format is not fixed then this is a hard problem

Nothing is hard in C. If the file was not a fixed format, you just add a loop, int and switch.

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