Question

我有这些多重错误和警告，我已经尝试过几乎所有事情并且无法弄明白。非常感谢您的帮助！这是我的代码：



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

int main()
{   
    /* Create Usable Variables */
    FILE *src_p, *dst_p;
    char src_file[20], dst_file[20];
    char c;

    /* Retrieve Source File Name From User */
    printf("Enter Source File Name:\n");
    fgets(src_file, 19, stdin);

    /* Attempt Opening Source File For Reading */
    if( (src_p = fopen(src_file, "r")) == NULL )
    {
        printf("ERROR: Source File Failed To Open...\n");
        return(-1);
    }

    /* Retrieve Destination File Name From User */
    printf("Enter Destination File Name:\n");
    fgets(dst_file, 19, stdin);

    /* Attempt Opening Destination File For Writing */
    if( (dst_p = fopen(dst_file, "w")) == NULL )
    {
        fclose(src_p);
        printf("ERROR: Destination File Failed To Open...\n");
        return(-2);
    }

    /* Copy Source File Contents Into Destination File */
    while( (c = fgetc(src_p)) != EOF )
        fputc(c, dst_file);

    /* Close Files On Success */
    fclose(src_p);
    fclose(dst_p);

    return 0;
}

#include <stdio.h> #include <stdlib.h> int main() { /* Create Usable Variables */ FILE *src_p, *dst_p; char src_file[20], dst_file[20]; char c; /* Retrieve Source File Name From User */ printf("Enter Source File Name:\n"); fgets(src_file, 19, stdin); /* Attempt Opening Source File For Reading */ if( (src_p = fopen(src_file, "r")) == NULL ) { printf("ERROR: Source File Failed To Open...\n"); return(-1); } /* Retrieve Destination File Name From User */ printf("Enter Destination File Name:\n"); fgets(dst_file, 19, stdin); /* Attempt Opening Destination File For Writing */ if( (dst_p = fopen(dst_file, "w")) == NULL ) { fclose(src_p); printf("ERROR: Destination File Failed To Open...\n"); return(-2); } /* Copy Source File Contents Into Destination File */ while( (c = fgetc(src_p)) != EOF ) fputc(c, dst_file); /* Close Files On Success */ fclose(src_p); fclose(dst_p); return 0; }

我尝试编译时的错误是：

copyfile.c：在函数'main'中： copyfile.c：44：3：警告：从不兼容的指针类型[默认启用]传递'fputc'的参数2 在copyfile.c中包含的文件中：1：0： /usr/include/stdio.h:573:12：注意：预期'struct FILE *'但参数类型为'char *'

非常感谢您的帮助！

Answer 1

在您的代码dst_file中char [20]是fopen，用于FILE *，获取您dst_p中存储的fputc(c, dst_file)。

而不是fputc(c, dst_p)尝试{{1}}。

Answer 2

您需要意识到，当您输入文件名时，您正在读取包含（取决于操作系统）换行符，回车符或两者的输入行。因此，您需要一种方便的方法来删除这些无关紧要的角色。

借用perl等人的想法，我喜欢chomp（），它从行的末尾删除'\ n'和'\ r'。

您还需要注意文件名与文件句柄，文件名上的fputc而不是文件句柄。

char [20]对于文件名来说相当小，尝试200+;并且您可能会发现“w +”将在不存在时创建输出文件;并将sizeof（变量）用于fgets大小，而不是硬编码大小。

这有效，

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
char* chomp(char* p)
{
    int len;
    if(!p) return(p);
    if( (len=strlen(p))<=0 ) return(p);
    if( p[len-1] == '\n' ) { p[--len] = '\0'; }
    if( p[len-1] == '\r' ) { p[--len] = '\0'; }
    return(p);
}
int main()
{
    /* Create Usable Variables */
    FILE *src_fh, *dst_fh;
    char src_fn[256+1], dst_fn[256+1];

    /* Retrieve Source File Name From User */
    printf("Enter Source File Name:\n");
    fgets(src_fn, sizeof(src_fn), stdin); chomp(src_fn);

    /* Attempt Opening Source File For Reading */
    if( (src_fh = fopen(src_fn, "r")) == NULL )
    {
        printf("ERROR: Source File %s Failed To Open...\n",src_fn);
        return(-1);
    }

    /* Retrieve Destination File Name From User */
    printf("Enter Destination File Name:\n");
    fgets(dst_fn, sizeof(dst_fn), stdin); chomp(dst_fn);

    /* Attempt Opening Destination File For Writing */
    if( (dst_fh = fopen(dst_fn, "w+")) == NULL )
    {
        fclose(src_fh);
        printf("ERROR: Destination File %s Failed To Open...\n",dst_fn);
        return(-2);
    }

    int ch;
    /* Copy Source File Contents Into Destination File */
    while( (ch = fgetc(src_fh)) != EOF )
    {
        fputc(ch, dst_fh);
    }

    /* Close Files On Success */
    fclose(src_fh);
    fclose(dst_fh);
    return 0;
}

将一个文件复制到c中的另一个错误中

2 个答案: