在调用函数in_read的时候出现了问题，调试的时候发现程序执行到这个函数处就不执行了，in_write是向文件内写一个3*3矩阵和一个3*1的矩阵。in_read是读出这两个矩阵的行数和列数。把in_read单独执行下发现好使，真是不知道怎么回事了，麻烦大家解下疑惑。
#include"stdio.h"
#include"stdlib.h"
#include"iostream.h"
#include"conio.h"

FILE *fp;
int **p1,**p2;
void in_write(FILE *fp);
int in_read(int h,int l,char w);

int main()
{
    int ah=0,al=0,yh=0,yl=0;
    char q;
    fp=fopen("in_r.txt","w+");                /*write numbers to file in_r*/
    printf("Please input the numbers.\n");
    in_write(fp);

    rewind(fp);
    puts("The end to write.\n");

    q='A';
    printf("%c",q);
    in_read(ah,al,q);                           /*read the matrix A*/

    q='Y';
    printf("%c",q);
    in_read(yh,yl,q);                           /*read vector Y*/
   
    return(0);
}

void in_write(FILE *fp)                       /*The function to write numbers*/
{
    int i,j,m=0;
    if(fp==NULL)
    {
        printf("open in_r error.\n");
        exit(0);
    }
    else
    {
        printf("Now input the matrix a.\n");
        for(i=1;i<=3;i++)
        {
            for(j=1;j<=3;j++)
            {
                scanf("%d ",&m);
                fprintf(fp,"%d ",m);
            }
            fputc('\n',fp);
        }
        fflush(stdin);
        printf("Then input vector Y\n");
        fputc('\n',fp);
        for(i=1;i<=3;i++)
        {
            scanf("%d ",&m);
            fprintf(fp,"%d ",m);
            fputc('\n',fp);
        }
    }
}

int in_read(int h,int l,char w)                           /*read the matrix*/                             
{
    int m,d=0,flag=0,c=0,A=0;
    h=0;
    l=0;
    char c1,c2;
    for(;flag==0;)
    {
        fscanf(fp,"%d",&m);
        fscanf(fp,"%c",&c1);
        c++;
        if(c1=='\n')
        {
            l=c;
            h++;
            if((h>1)&&c!=d)
            {
                A=1;
                break;
            }
            fscanf(fp,"%c",&c2);
            d=c;
            c=0;
            if(c2=='\n')
                flag=1;
            else
                fseek(fp,-1l,1);
        }
    }
    printf("In %c ah=%d,al=%d\n",w,h,l);
    return(0);

}