How to read this kind of file by using C.

[qingxing2005]

Dear all,

I met one problem when reading the following context file by using C. E.g. abc: 123123,123123123,123123123

I use the statement, i.e. fscanf(fp_t, "%s %d %d %d", stringA, cl[0], cl[1], c[2]);

However, the values cannot be read and put to the variable cl[1], cl[2]. Only reading value and putting it to cl[0] is feasible.

Is there anyone can help a little?

Thanks in advance,

 

[cpjust]

Read each line into a string, then parse the string (maybe strtok() would help), then use something like atoi() to convert each sub-string into a number...

 

[ArkM]

And don't forget to add get address (&) operation for all variables (except arrays) in scanf family arg list.

It's interesting that in some implementations (MS and may Unix) you may use %s specificator non-standard extension:

fscanf(fp_t,"%[^:]%d,%d,%d", stringA,&cl[0],&cl[1],&c[2]);

It's a very dangerous (and non-standard) code: for example, no scanf return code check (do it in all cases). Better use cpjust's good advice.

 

[qingxing2005]

Hey,

I also tried following code, it works somewhat for my case. However, with something little not. See followings.

The context file to be read is, i.e.

abc:1111111111,2222222222,3333333333,4444444444,5555555555,6666666666,
d: 0
efg: 1111111111,2222222222,3333333333,4444444444,5555555555,6666666666

1. the outputs of reading 4444444444,5555555555 are 149477148 1260588259. by using this sentence,

fscanf(fp_t, "%s %10d , %10d , %10d , %10d , %10d , %10d", stringA, &cl[0], &cl[1], &c[2], &cl[3], &cl[4], &c[5]);

It is weird.

 

[Salem]

You're running into integer overflow, as explained on cprogramming.com already.


--
If you dance barefoot on the broken glass of undefined behaviour, you've got to expect the occasional cut.