How can I get get the owner name and group name of a file on a Linux filesystem using C++? The stat() call only gives me owner ID and group ID but not the actual name.
-rw-r--r--. 1 john devl 3052 Sep 6 18:10 blah.txt
How can I get 'john' and 'devl' programmatically?
Jonathan Leffler
Use getpwuid() and getgrgid().
#include <pwd.h>
#include <grp.h>
#include <sys/stat.h>
struct stat info;
stat(filename, &info); // Error check omitted
struct passwd *pw = getpwuid(info.st_uid);
struct group *gr = getgrgid(info.st_gid);
// If pw != 0, pw->pw_name contains the user name
// If gr != 0, gr->gr_name contains the group name
One way would be to use stat() to get the uid of a file and then getpwuid() to get the username as a string.
来源：https://stackoverflow.com/questions/7328327/how-to-get-files-owner-name-in-linux-using-c