fgetc  统计行号

 23     FILE* fp=fopen("./1.c","r");24     if(fp==0)25     {26         perror("错误原因");27         return -1;28     }29     int count=0;30     while(1)31     {32         char retval=fgetc(fp);33         if(retval==EOF)34         {35             break;36         }37         else if(retval=='\n')38         {39             count++;40         }41     }42     printf("count=%d\n",count);43     fclose(fp);44 45     return 0;46 }   

fgetc/fputc 文件拷贝

 23     FILE* rfp=fopen("./1.c","r");24     FILE* wfp=fopen("./11.c","w");25     if(rfp==0||wfp==0)26     {27         perror("错误原因");28         return -1;29     }30     while(1)31     {32         char ch=fgetc(rfp);33         if(ch==EOF)34         {35             break;36         }37         fputc(ch,wfp);38     }39     fclose(rfp);40     fclose(wfp);41     return 0;                                                               42 }

fscanf/fprintf 文件拷贝

 21 int main(int argc, const char *argv[])22 {23     FILE* rfp=fopen("11.c","r");24     FILE* wfp=fopen("111.c","w");25     if(rfp==0||wfp==0)26     {27         perror("错误原因");28         return -1;29     }30     while(1)31     {32         char ch=0;33         int retval=fscanf(rfp,"%c",&ch);34         if(retval==EOF)35         {36             break;37         }38         fprintf(wfp,"%c",ch);                                               39     }

fgets读的过程

 23     FILE* fp=fopen("./1.c","r");24     if(fp==0)25     {26         perror("错误原因");27         return -1;28     }29     char str[10]="";30     while(1)31     {32         char* p=fgets(str,10,fp);33         if(p==NULL)34         {35             break;36         }37         printf("%s\n",str);38     }                                                                       39     //  printf("%s\n",str);40     fclose(fp);41     return 0;42 }

fgets统计行号

 24     FILE* fp=fopen("./1.c","r");25     if(fp==0)26     {27         perror("错误原因");28         return -1;29     }30     int count=0;31     char str[2]="";32     while(1)33     {34         char* p=fgets(str,2,fp);35         if(p==NULL)36         {37             break;38         }39         else if(str[0]=='\n')40         {41             count++;42         }43     }44     printf("count=%d\n",count);45     return 0;46 }  

fread/fwrite/fseek  红色旗

 23     FILE* fp=fopen("./SYK6XNF[HINYIE}OP)_6I96.bmp","r");24     int size=0;25     int width=0;26     int height=0;27     fseek(fp,2,SEEK_SET);28     fread(&size,4,1,fp);29     printf("图片总大小为：%d\n",size);30 31     fseek(fp,18,SEEK_SET);32     fread(&width,4,1,fp);33     fread(&height,4,1,fp);34     printf("width=%d,height=%d\n",width,height);35 36     unsigned char bgr[3]={0,0,255};37     fp=fopen("./SYK6XNF[HINYIE}OP)_6I96.bmp","r+");38     fseek(fp,54,SEEK_SET);39     for(int i=0;i<width;i++)40     {41         for(int j=0;j<height;j++)42         {                                                                   43             fwrite(bgr,3,1,fp);44         }45     }46     fclose(fp);