read_serialno

#include 
#include 
#include 
#include 
#include 

static int getSNNumber(char *pBuf)
{
    int ret,cm;
    char *ptr;
    int fp; 

    fp = open("file.txt", O_RDWR|O_NONBLOCK);
    if(fp>0) {
        ret=read(fp,pBuf,100);
        ptr=strstr(pBuf,"+QCSN:");
        if(ptr==NULL) return -2; 
        while (*ptr++ != '"');
        while(*ptr != '"') {
            *pBuf++ = *ptr++;
        }   
        *pBuf = 0;
        close(fp);
        return 0;
    }
    return -1;
}

int main()
{
    char pBuf[100];
    char *p = pBuf;
    int ret;
    memset(pBuf, 0, sizeof(pBuf));
    ret = getSNNumber(p);
    if (ret < 0) {
        printf("qyc, failed\n");
    }else
        printf("%s\n", pBuf);
    
    return 0;
}