C/C++ 获取文件长度（转）

来源：互联网发布：网络公开课计算机视觉编辑：程序博客网时间：2024/04/28 03:56

C/C++ 获取文件长度（转）（一）对文件操作时有时获得文件的大小时必要的.下面是获得其大小小的较简单方法.#include //C 语言头文件#include //for system();using namespace std;int main(){int handle;handle = open("test.txt", 0x0100); //open file for readlong length = filelength(handle); //get length of filecout<<"file length in bytes:"<#include //for windows apiusing namespace std;int main(){//用API函数CreateFile()创建文件句柄HANDLE fhadle = CreateFile("file.txt", //文件名或路径0,0,0,OPEN_EXISTING, //文件存在则打开并读取0,0);DWORD size = GetFileSize(fhadle,0);cout<<"size:"<#include using namespace std;int main(int argc, char* argv[]){ifstream in("file.txt");in.seekg(0, ios::end); //设置文件指针到文件流的尾部streampos ps = in.tellg(); //读取文件指针的位置cout << "File size: " << ps << endl;in.close(); //关闭文件流return 0;} （四）在VC中，CFILE的GetLength()函数可直接得到大小：CFile cf; // Attempt to open thefile for reading.if( !cf.Open( pszFilename, CFile::modeRead ) )return( FALSE ); // Get the size of the file and store// in a local variable. .DWORD dwSize;dwDibSize = cf.GetLength(); (五)#include ;#include ;longget_filesize(char *filename){struct stat f_stat;if (stat(filename, &f_stat) == -1) {return -1;}return (long)f_stat.st_size;}(六)int main(void){struct stat statbuf;FILE *stream;/* open a file for update */if ((stream = fopen(FILENAME, "w+")) == NULL){fprintf(stderr, "Cannot open output file./n");return(1);}/* get information about the file */stat(FILENAME, &statbuf);fclose(stream);/* display the information returned */if (statbuf.st_mode & S_IFCHR)printf("Handle refers to a device./n");if (statbuf.st_mode & S_IFREG)printf("Handle refers to an ordinary file./n");if (statbuf.st_mode & S_IREAD)printf("User has read permission on file./n");if (statbuf.st_mode & S_IWRITE)printf("User has write permission on file./n");printf("Drive letter of file: %c/n", 'A'+statbuf.st_dev);printf("Size of file in bytes: %ld/n", statbuf.st_size);printf("Time file last opened: %s/n", ctime(&statbuf.st_ctime));return 0;}(七)#include ;#include ;#include ;#include ;#include ;int main(void){int handle;char msg[] = "This is a test";char ch;/* create a file */handle = open("TEST.$$$", O_CREAT | O_RDWR, S_IREAD | S_IWRITE);/* write some data to the file */write(handle, msg, strlen(msg));/* seek to the beginning of the file */lseek(handle, 0L, SEEK_SET);/* reads chars from the file until we hit EOF */do{read(handle, &ch, 1);printf("%c", ch);} while (!eof(handle));close(handle);return 0;}来自: http://hi.baidu.com/ignorer/blog/item/274276091ab8eea32fddd42c.html