C- Is it right to read binary txt file?

Question

I am beginner of C language.

I am trying to read a binary txt file.

When I just opened the txt file directly, I saw it

• 젂 8 F ? ㎲?잤Oタsp쑴톧숴沛=)麴퓠5?r!오?쏠AD풠-V욕?C珞?|붆拂쟬v????걀신v?@n풶1c퓋?>p璉>5쾳엥V壤?뾅A癬A?Αw 殆퀃[??픫퇡원?퓅V맙°쐴??閣?W條>걬벩3쁂횖?l?젖?옜鸚?d乍?涌h??伽?Y뤍XK?묠?RT?테?@숦 ?vY햙y?kz'?n?6註웍Qt??*풯?인$???쾹y옇왯?L쁂碻?祠녋Dm+작\藪왱여?픻9c욋??출풛 궭母?좣?孔8퓎뒜C=瑾A??+샓?쇏\꾟퐾岫?j?s蕣풖M픑?앝I폹?=?f쏜 쌒뎠??빦갈i?_$?掠?;????2 & 풰Е?U윰i녉U?푂?풧+쁂-暉A倫겵헳퐉lg퓾닆욋ⓨ풇짡?믳빢쨒榕:@?뺠?쏱요p殆쩋쁂M됆A??욢??돽p瑥푢

Yes, the things in the txt file seem to be weird because it presents binary things.

The file consists of header and data.

The Header are

nSamples - number of samples in file (4-byte integer)

sampPeriod - sample period in 100ns units (4-byte integer)

sampSize - number of bytes per sample (2-byte integer)

parmKind - a code indicating the sample kind (2-byte integer)

and 4byte float type of data part.

My code is really doing well about the Header part.

but I don't know why it is going worse in the data part.

The data part seems to be wrong in my code because they have same values except data[0]

Actually, they all have different values.

#include <stdio.h> 
#include <stdlib.h> // exit() 



    int main(void) 
    { 

    FILE *a; 



    int abc=1; 
    int ch; 
    int size; 
    int k; 

    float* data; 
    long* nSamples; 
    long* sampPeriod; 
    short* sampSize; 
    short* sampKind; 

    nSamples=(long*) malloc(sizeof(long)); 
    sampPeriod=(long*) malloc(sizeof(long)); 
    sampSize=(short*) malloc(sizeof(short)); 
    sampKind=(short*) malloc(sizeof(short)); 
    data=(float*) malloc(sizeof(float)*10); 
    //I Just wanted to check a few values 

    if ((a = fopen("noalter.txt", "rb")) == NULL) { 
     fputs("error!", stderr); 
     exit(1); 
    } 

    fread(nSamples,sizeof(long),1,a); 
    fread(sampPeriod,sizeof(long),1,a); 
    fread(sampSize,sizeof(short),1,a); 
    fread(sampKind,sizeof(short),1,a); 

    fread(data,sizeof(float),1,a); 
    fread(data,sizeof(float),1,a); 
    fread(data,sizeof(float),1,a); 

    printf("%ld \n",nSamples[0]); 
    printf("%ld \n",sampPeriod[0]); 
    printf("%d \n", sampSize[0]); 
    printf("%d \n", sampKind[0]); 
    printf("%f \n", data[0]); 
    printf("%f \n", data[1]); 
    printf("%f \n", data[2]); //I Just wanted to check a few values 


    fclose(a); 
    free(nSamples); 
    free(sampPeriod); 
    free(sampSize); 
    free(sampKind); 

    return 0; 
    } 

Answer 1

When reading the data, you read into the same position of data all three times. You should do e.g.

fread(&data[0], sizeof(data[0]), 1, a); 
fread(&data[1], sizeof(data[1]), 1, a); 
fread(&data[2], sizeof(data[2]), 1, a); 

Or just read all ten entries you have allocated:

fread(data, sizeof(data[0]), 10, a); 

Answer 2

If you are using Linux the contents of the binary file can also be used using cat command.