How can i optimize the follow function?

[pilafi]

char start=0;
    char isfloat=0;
    char tmp_num[10];
    int i=0,j=0;
    char *end;
 
    memset(tmp_num,0,10);
 
    end=(*str)+strlen(*str);
 
    while(((*str)++)<=end)
    { 
        if( isdigit(**str) )
 
        {
            start=1;
            tmp_num[j] = **str;
            j=j+1;
        }
        if( ispunct(**str) && start==1)
 
        {
            isfloat=1;
            tmp_num[j] = **str;
            j=j+1;
        }
 
        if( (**str==' ') || (**str==0) )
        {
            if(isfloat==1 && start==1)
            {
                *d=atof(tmp_num);
                return 0;
            }
            if(*(*str+1)==0)
            {
                return 1;
            }
            start=0;
            isfloat=0;
            j=0;
            memset(tmp_num,0,10);
        }
 
    }    
 
    return 1;
}

I have large data sets and this functios creates problems because of the isdigit and ispunct function. Do you have any idea to replace them??
Thnx guys!!

[Cucumber]

Well, you can save a call to

memset(tmp_num,0,10);

using

tmp_num[0]=0;
and doing
tmp_num[j++] = **str;
tmp_num[j]=0;

I dont know whether that would help.

Anyway, try using some optimization flag in your compiler, like -O2 or -O3 and see if your program speed improves.

[pilafi]

I tried to use the optimization flags, but the speed doesnt change. I forgot to give you a detail that this function is a function for getting the next double you find in the file. It works normally, but i have some files with a lot of doubles, really lot and my program crasses in these files. Please help guys!!Thnx!!