Parse file fscanf

Question

I want to parse from a file that has the following format (it may change) the number that is after t= (e.g 19625):

3a 01 4b 46 7f ff 06 10 42 : crc=42 YES\n
3a 01 4b 46 7f ff 06 10 42 t=19625

int t;
fp=fopen("text","r");
fscanf(fp,"t=%d",&t);
fclose(fp);
printf("%d\n",t);

does not give the output.. Any suggestions?

Tokenize on white space, `strstr` for `t=` then parse that then `strtol` or something along those lines. — Scotty Bauer, Dec 09 '13 at 21:48

score 1 · Answer 1 · answered Dec 10 '13 at 00:33

1

modify like this

    int t;
    char buff[32];
    FILE *fp=fopen("text","r");
    while(EOF!=fscanf(fp, "%s", buff)){
        if(1==sscanf(buff, "t=%d",&t)){
            break;
        }
    }
    fclose(fp);
    printf("%d\n",t);

answered Dec 10 '13 at 00:33

BLUEPIXY

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score 0 · Answer 2 · edited May 23 '17 at 10:32

0

Here, the right keyword is "hexadecimal"

see How do I read hex numbers into an unsigned int in C

see http://www.cplusplus.com/reference/cstdio/fscanf/

Try

  int readt[4];
  fscanf(fp,"t=%x %x %x %x",&readt[0],&readt[1],&readt[2],&readt[3]);
  t=((256*readt[0]+readt[1])*256+readt[2])*256+readt[3];
  printf("t=%d\n",t);

Bye,

Francis

edited May 23 '17 at 10:32

Community

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answered Dec 09 '13 at 22:14

francis

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score 0 · Answer 3 · answered Nov 10 '16 at 09:50

0

As long as the file doesn't contain a t before the t=, you could simply replace the

fscanf(fp,"t=%d",&t);

with

fscanf(fp, "%*[^t]t=%d", &t);

answered Nov 10 '16 at 09:50

Armali

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Parse file fscanf

3 Answers3