字符指针问题

[pp25210]

#include<stdio.h>
#include<ctype.h>    //在vc6.0运行，为什么没有这个头文件toupper（）函数还可以继续使用
#include<stdlib.h>   //exit()

int main()
{
    FILE *sourcef,*aimf;
    int ch;
    int count = 0;
    int flag = 0;
    char *argv[2];      //为什么将这里的二维数组改成一维指针数组（ 即    *argv[2]），后面程序不变，就会出现运行错误？
                        //在编译时出现warning C4700: local variable 'argv' used without having been initialized

    while(flag == 0 )
    {
        puts("input source file name:");
        gets(argv[0]);
        puts("input aim file name:");
        gets(argv[1]);

       if((sourcef = fopen(argv[0],"r")) == NULL)     //open  two file
       {
           printf("open %s error.\n",argv[0]);
           continue;
       }
       if((aimf = fopen(argv[1],"w")) == NULL)
       {
           printf("open %s error.\n",argv[1]);
           continue;
       }
       flag = 1;
    }

    //copy file
    while((ch = getc(sourcef)) != EOF)
    {
        putc(toupper(ch),aimf);
        count++;
    }

    //judging EOF
    if(feof(sourcef) == 0)
    {
        fprintf(stdout,"error in reading file %s \n.",argv[0]);
        exit (1);
    }
    if(ferror(sourcef) != 0)
    {
        fprintf(stdout,"error in writing file %s \n.",argv[0]);
        exit(1);
    }
    fputs("copy successfuly\n,",stdout);
    fprintf(stdout,"file %s has %d characters.\n",argv[0],count);
    fclose(sourcef);
    fclose(aimf);


    return 0;
}

[就想叫yoko]

char *argv[2];      //为什么将这里的二维数组改成一维指针数组（ 即    *argv[2]），后面程序不变，就会出现运行错误？
	argv[0] = (char*)malloc(sizeof(char)*128);
	argv[1] = (char*)malloc(sizeof(char)*128);

[CrackValue]

学习受教了

[如此美丽的你]

    while(flag == 0 )
    {
        puts("input source file name:");
        gets(argv[0]);//这里argv[0]没有分配内存空间是个野指针，二维数组会自动分配空间
        puts("input aim file name:");
        gets(argv[1]);//同上

       if((sourcef = fopen(argv[0],"r")) == NULL)     //open  two file
       {
           printf("open %s error.\n",argv[0]);
           continue;
       }
       if((aimf = fopen(argv[1],"w")) == NULL)
       {
           printf("open %s error.\n",argv[1]);
           continue;
       }
       flag = 1;
    }

[AnYidan]

#include<ctype.h>    //在vc6.0运行，为什么没有这个头文件toupper（）函数还可以继续使用

可能<ctype.h> 被包含在别的头文件中