c - 使用 fclose() 时出现段错误

Question

我是 C 新手，我正在尝试将输出写入文件。当我尝试关闭输出文件时，似乎遇到了段错误。我按照与一些示例相同的步骤打开文件并分配内存。

预先感谢您的帮助。这是代码:

#include <stdio.h>
#include <stdlib.h>
#include <math.h>

#define pi      4*atan(1)

FILE  *my_file_1; // Output file (*.txt)
FILE  *my_file_2; // Output file (*.txt)

int main()
{
    int nx, ny, npts;
    int niter;


    double dt, w, height, d_o, h, factork, dVol;
    double rho_o, g, lamda, po, co, p1, p2, r; // Fluid Properties


    double *x, *y, *u, *v, *du, *dv, *rho, *drho, *p, *m;
    double en_x, en_y, dw, dwx, dwy, sum1, sum2, sum3;
    int i, j, k;


    //Parameters

    height = 0.2;  //Height
    w = 0.1;  //width
    nx = 20;  //Number of particles x-dir
    ny = 40;  //Number of particles y-dir
    npts = nx*ny;// Total number of particles
    d_o = w / nx; // Distance between particles
    dt = 0.00002;
    dVol = 4 * pow((d_o / 2), 2);

    // boundary
    double L,height_wall,*xw1,*xw2,*xb,*yw1,*yw2,*yb;
    int nyw1,nyw2,nxb;
    int nrows,np1,np2,npb;

    L=0.8;
    height_wall=0.4;
    nrows=3;

    nyw1=height_wall/d_o;
    nyw2=height_wall/d_o;
    nxb=L/d_o;
    np1=nrows*nyw1;
    np2=nrows*nyw2;
    npb=nrows*nxb;
     printf("%d\n",npb);
    // getchar();


    h = 1.33*d_o; // Smoothing length
    factork = 2; //Constant for kernell

    //Fluid
    rho_o = 1000;
    g = 9.81;
    lamda = 1;
    po = 101325;
    co = 30;

    x = (double*)malloc(npts*sizeof(int));
    y = (double*)malloc(npts*sizeof(int));
    u = (double*)malloc(npts*sizeof(int));
    v = (double*)malloc(npts*sizeof(int));
    rho = (double*)malloc(npts*sizeof(int));
    du = (double*)malloc(npts*sizeof(int));
    dv = (double*)malloc(npts*sizeof(int));
    drho = (double*)malloc(npts*sizeof(int));
    p = (double*)malloc(npts*sizeof(int));
    m = (double*)malloc(npts*sizeof(int));

    //boundaries
    xw1 = (double*)malloc(np1*sizeof(int));
    yw1= (double*)malloc(np1*sizeof(int));
    xw2 = (double*)malloc(np2*sizeof(int));
    yw2= (double*)malloc(np2*sizeof(int));

    xb = (double*)malloc(npb*sizeof(int));
    yb= (double*)malloc(npb*sizeof(int));


    my_file_1 = fopen("org.txt", "w");
    my_file_2 = fopen("bound.txt", "w");

// Particles
    for (i = 0; i<ny; i++)
    {
        for (j = 0; j<nx; j++)
        {
            x[nx*i + j] = d_o / 2 + j*d_o;
            y[nx*(i)+j] = d_o / 2 + i*d_o;
            // printf("%20.18f %20.18f\n",x[nx*i+j],y[nx*(i)+j]);
            //printf("%7.4f %7.4f\n ", x[nx*i + j], y[nx*(i)+j]);
            fprintf(my_file_1, "%7.4f %7.4f\n ", x[nx*i + j], y[nx*(i)+j]);

        }
    }



    //Boundries

    //Left wall

    for (i = 0; i<nyw1; i++)
    {
        for (j = 0; j<nrows; j++)
        {
            xw1[nrows*i + j] = -L/2+d_o / 2 + j*d_o;
            yw1[nrows*(i)+j] = d_o / 2 + i*d_o;
            // printf("%20.18f %20.18f\n",x[nx*i+j],y[nx*(i)+j]);
            //printf("%7.4f %7.4f\n ", x[nx*i + j], y[nx*(i)+j]);
            fprintf(my_file_2, "%7.4f %7.4f\n ", xw1[nrows*i + j], yw1[nrows*(i)+j]);

        }
    }

     //Right wall

    for (i = 0; i<nyw2; i++)
    {
        for (j = 0; j<nrows; j++)
        {
            xw2[nrows*i + j] = L/2-4*d_o+3*d_o / 2 + j*d_o;
            yw2[nrows*(i)+j] = d_o / 2 + i*d_o;
            // printf("%20.18f %20.18f\n",x[nx*i+j],y[nx*(i)+j]);
            //printf("%7.4f %7.4f\n ", x[nx*i + j], y[nx*(i)+j]);
            fprintf(my_file_2, "%7.4f %7.4f\n ", xw2[nrows*i + j], yw2[nrows*(i)+j]);

        }
    }

        //Bottom wall
            for (i = 0; i<nrows; i++)
    {
        for (j = 0; j<nxb; j++)
        {
            xb[nxb*i + j] = -L/2+d_o/2 + j*d_o;
            yb[nxb*i+j] = -4*d_o / 2 +i*d_o;
             //printf("%d %d\n",i,j);
             printf("%d %d\n",i,j);
             printf("%20.18f %20.18f\n",xb[nxb*i+j],yb[nxb*(i)+j]);
            //printf("%7.4f %7.4f\n ", x[nx*i + j], y[nx*(i)+j]);
            fprintf(my_file_2, "%7.4f %7.4f\n ", xb[nxb*i + j], yb[nxb*(i)+j]);

        }
    }

fclose(my_file_1)
fclose(my_file_2)
}

Answer 1

下面是对代码的修改，修复了内存分配，并修复了导致代码无法编译的错误!并且风格发生了很多变化。我还删除了所有不活动的代码，这是提交程序时的一个好主意，以便人们可以专注于问题。我还对您的 fopen() 和 fclose() 调用进行了错误检查，因此如果出现其他问题，您应该获取更多信息。下面的代码运行完成，没有错误:

#include <stdio.h>
#include <stdlib.h>
#include <math.h>

#define pi (4 * atan(1))

#define ORG_FILE_NAME "org.txt"
#define BOUND_FILE_NAME "bound.txt"

int main()
{
    // Parameters

    double w = 0.1; // Width
    int nx = 20; // Number of particles x-dir
    int ny = 40; // Number of particles y-dir
    int npts = nx * ny; // Total number of particles
    double d_o = w / nx; // Distance between particles

    // Boundary

    double L = 0.8;
    double height_wall = 0.4;
    int nrows = 3;

    int nyw1 = height_wall / d_o;
    int nyw2 = height_wall / d_o;
    int nxb = L / d_o;

    int np1 = nrows * nyw1;
    int np2 = nrows * nyw2;
    int npb = nrows * nxb;
    printf("%d\n", npb);

    // Fluid

    double *x = calloc(npts, sizeof(double));
    double *y = calloc(npts, sizeof(double));

    // Boundaries

    double *xw1 = calloc(np1, sizeof(double));
    double *yw1 = calloc(np1, sizeof(double));
    double *xw2 = calloc(np2, sizeof(double));
    double *yw2 = calloc(np2, sizeof(double));

    double *xb = calloc(npb, sizeof(double));
    double *yb = calloc(npb, sizeof(double));


    FILE *my_file_1 = fopen(ORG_FILE_NAME, "w"); // Output file (*.txt)

    if (my_file_1 == NULL)
    {
        perror(ORG_FILE_NAME);
        return(EXIT_FAILURE);
    }

    FILE *my_file_2 = fopen(BOUND_FILE_NAME, "w"); // Output file (*.txt)

    if (my_file_2 == NULL)
    {
        perror(BOUND_FILE_NAME);
        return(EXIT_FAILURE);
    }

    // Particles

    for (int i = 0; i < ny; i++)
    {
        for (int j = 0; j < nx; j++)
        {
            x[nx * i + j] = d_o / 2 + j * d_o;
            y[nx * i + j] = d_o / 2 + i * d_o;
            fprintf(my_file_1, "%7.4f %7.4f\n", x[nx * i + j], y[nx * i + j]);
        }
    }

    // Boundries

    // Left wall

    for (int i = 0; i < nyw1; i++)
    {
        for (int j = 0; j < nrows; j++)
        {
            xw1[nrows * i + j] = -L / 2 + d_o / 2 + j * d_o;
            yw1[nrows * i + j] = d_o / 2 + i * d_o;
            fprintf(my_file_2, "%7.4f %7.4f\n", xw1[nrows * i + j], yw1[nrows * i + j]);

        }
    }

    // Right wall

    for (int i = 0; i < nyw2; i++)
    {
        for (int j = 0; j < nrows; j++)
        {
            xw2[nrows * i + j] = L / 2 - 4 * d_o + 3 * d_o / 2 + j * d_o;
            yw2[nrows * i + j] = d_o / 2 + i * d_o;
            fprintf(my_file_2, "%7.4f %7.4f\n", xw2[nrows * i + j], yw2[nrows * i + j]);
        }
    }

    // Bottom wall

    for (int i = 0; i < nrows; i++)
    {
        for (int j = 0; j < nxb; j++)
        {
            xb[nxb * i + j] = -L / 2 + d_o / 2 + j * d_o;
            yb[nxb * i + j] = -4 * d_o / 2 + i * d_o;
            fprintf(my_file_2, "%7.4f %7.4f\n", xb[nxb * i + j], yb[nxb * i + j]);

        }
    }

    if (fclose(my_file_1) != 0)
    {
        perror(ORG_FILE_NAME);
        return(EXIT_FAILURE);
    }

    if (fclose(my_file_2) != 0)
    {
        perror(BOUND_FILE_NAME);
        return(EXIT_FAILURE);
    }

    return EXIT_SUCCESS;
}