How can I determine the owner of a file or directory using boost filesystem?

Possible Duplicate: Get file's owner and group using boost I'd like to use boost::filesystem to determine which files and directories/ folders are owned by a particular user. I need to do this on both Linux (ext3) and Windows (NTFS) filesystems. How can I get the user identifier for a specified path using boost::filesystem? Thanks in advance. Edit: Code derived from selected answer: ``` #include <iostream> #include <string> #ifdef LINUX #include <pwd.h> #include <grp.h> #include <sys/stat.h> #else #include <stdio.h> #include <windows.h> #include <tchar.h> #include "accctrl.h" #include "aclapi.h" #pragma comment(lib, "advapi32.lib") #endif bool getOwner(const std::string &Filename, std::string &Owner) { #ifdef LINUX struct stat FileInfo; stat(Filename.c_str(), &FileInfo); struct passwd *UserDatabaseEntry = getpwuid(FileInfo.st_uid); struct group *GroupDatabaseEntry = getgrgid(FileInfo.st_gid); // if (UserDatabaseEntry != 0) { Owner = UserDatabaseEntry->pw_name; return true; } else { return false; } #else DWORD dwRtnCode = 0; PSID pSidOwner = NULL; BOOL bRtnBool = TRUE; LPTSTR AcctName = NULL; LPTSTR DomainName = NULL; DWORD dwAcctName = 1, dwDomainName = 1; SID_NAME_USE eUse = SidTypeUnknown; HANDLE hFile; PSECURITY_DESCRIPTOR pSD = NULL; // Get the handle of the file object. hFile = CreateFile( TEXT(Filename.c_str()), GENERIC_READ, FILE_SHARE_READ, NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL); // Check GetLastError for CreateFile error code. if (hFile == INVALID_HANDLE_VALUE) { DWORD dwErrorCode = 0; dwErrorCode = GetLastError(); _tprintf(TEXT("CreateFile error = %d\n"), dwErrorCode); return false; } // Get the owner SID of the file. dwRtnCode = GetSecurityInfo( hFile, SE_FILE_OBJECT, OWNER_SECURITY_INFORMATION, &pSidOwner, NULL, NULL, NULL, &pSD); // Check GetLastError for GetSecurityInfo error condition. if (dwRtnCode != ERROR_SUCCESS) { DWORD dwErrorCode = 0; dwErrorCode = GetLastError(); _tprintf(TEXT("GetSecurityInfo error = %d\n"), dwErrorCode); return false; } // First call to LookupAccountSid to get the buffer sizes. bRtnBool = LookupAccountSid( NULL, // local computer pSidOwner, AcctName, (LPDWORD)&dwAcctName, DomainName, (LPDWORD)&dwDomainName, &eUse); // Reallocate memory for the buffers. AcctName = (LPTSTR)GlobalAlloc( GMEM_FIXED, dwAcctName); // Check GetLastError for GlobalAlloc error condition. if (AcctName == NULL) { DWORD dwErrorCode = 0; dwErrorCode = GetLastError(); _tprintf(TEXT("GlobalAlloc error = %d\n"), dwErrorCode); return false; } DomainName = (LPTSTR)GlobalAlloc( GMEM_FIXED, dwDomainName); // Check GetLastError for GlobalAlloc error condition. if (DomainName == NULL) { DWORD dwErrorCode = 0; dwErrorCode = GetLastError(); _tprintf(TEXT("GlobalAlloc error = %d\n"), dwErrorCode); return false; } // Second call to LookupAccountSid to get the account name. bRtnBool = LookupAccountSid( NULL, // name of local or remote computer pSidOwner, // security identifier AcctName, // account name buffer (LPDWORD)&dwAcctName, // size of account name buffer DomainName, // domain name (LPDWORD)&dwDomainName, // size of domain name buffer &eUse); // SID type // Check GetLastError for LookupAccountSid error condition. if (bRtnBool == FALSE) { DWORD dwErrorCode = 0; dwErrorCode = GetLastError(); if (dwErrorCode == ERROR_NONE_MAPPED) { _tprintf(TEXT("Account owner not found for specified SID.\n")); } else { _tprintf(TEXT("Error in LookupAccountSid.\n")); } return false; } else if (bRtnBool == TRUE) { // Print the account name. _tprintf(TEXT("Account owner = %s\n"), AcctName); Owner = AcctName; return true; } #endif return false; } int main(int argc, char *argv[]) { std::string Filename = argv[0]; if (argc > 1) { Filename = argv[1]; } std::cout << "File " << Filename << " is owned by: "; // std::string Owner; bool OK = getOwner(Filename, Owner); if (OK) { std::cout << Owner << "." << std::endl; } else { std::cout << "Unknown." << std::endl; } return 0; } ```