编辑代码

#include <stdio.h>
#include <errno.h>
#include <string.h>

int main(){
    FILE * pf = fopen("test.txt","w");
    if(pf == NULL){
        printf("%s",strerror(errno));
    }
    fputc('c',pf);
    fclose(pf);
    pf = fopen("test.txt","r");
    int ch  =fgetc(pf);
    printf("%c\n",ch);
    fclose(pf);
    printf("成功输入");


    return 0;
}