Linux gets the current user information function __oracle

Http://www.cnblogs.com/dirt2/p/5999842.html

Turn from: http://net.pku.edu.cn/~yhf/linux_c/function/07.html

	Endgrent (Close group file)
Related functions	Getgrent,setgrent
Table header File	#include <grp.h> #include <sys/types.h>
Defining functions	void endgrent (void);
Function description	Endgrent () is used to close the password file opened by Getgrent ().
return value
Additional Instructions
Example	Please refer to getgrent () and Setgrent ().
	Endpwent (Close password file)
Related functions	Getpwent,setpwent
Table header File	#include <pwd.h> #include <sys/types.h>
Defining functions	void endpwent (void);
Function description	Endpwent () is used to close the password file opened by Getpwent ().
return value
Additional Instructions
Example	Please refer to getpwent () and Setpwent ().
	Endutent (Close utmp file)
Related functions	Getutent,setutent
Table header File	#include <utmp.h>
Defining functions	void endutent (void);
Function description	Endutent () is used to close the Utmp file that was opened by Getutent.
return value
Additional Instructions
Example	Please refer to getutent ().
	Fgetgrent (read group format from the specified file)
Related functions	Fgetpwent
Table header File	#include <grp.h> #include <stdio.h> #include <sys/types.h>
Defining functions	struct Group * getgrent (FILE * stream);
Function description	Fgetgrent () reads a row of data from the file specified by the parameter stream and returns the data in the group structure. The file specified by the parameter stream must be in the same format as, Etc/group. Group structure definition please refer to getgrent ().
return value	Returns the group structure data, or null if returned, indicating no data, or an error occurred.
Example	#include <grp.h> #include <sys/types.h> #include <stdio.h> Main () { struct group *data; FILE *stream; int i; stream = fopen ("/etc/group", "R"); while (data = Fgetgrent (stream))!=0) { i=0; printf ("%s:%s:%d:", Data->gr_name,data->gr_passwd,data->gr_gid); while (Data->gr_mem[i]) printf ("%s,", data->gr_mem[i++]); printf ("\ n"); } Fclose (stream); }
Perform	Root:x:0:root, Bin:x:1:root,bin,daemon Daemon:x:2:root,bin,daemon Sys:x:3:root,bin,adm Adm:x:4:root,adm,daemon Tty:x:5 Disk:x:6:root Lp:x:7:daemon,lp Mem:x:8 Kmem:x:9 Wheel:x:10:root Mail:x:12:mail News:x:13:news Uucp:x:14:uucp Man:x:15 Games:x:20 Gopher:x:30 DIP:X:40: Ftp:x:50 NOBODY:X:99:
	Fgetpwent (read password format from specified file)
Related functions	Fgetgrent
Table header File	#include <pwd.h> #include <stdio.h> #include <sys/types.h>
Defining functions	struct passwd * fgetpwent (FILE *stream);
Function description	Fgetpwent () reads a row of data from the file specified by the parameter stream, and then returns the data as a passwd structure. The file specified by the parameter stream must be in the same format as/etc/passwd. passwd structure definition refer to getpwent ().
return value	Returns the passwd structure data, if returned null indicates no data, or an error occurred.
Example	#include <pwd.h> #include <sys/types.h> Main () { struct passwd *user; FILE *stream; stream = fopen ("/etc/passwd", "R"); while (user = Fgetpwent (stream))!=0) { printf ("%s:%d:%d:%s:%s:%s\n", User->pw_name,user->pw_uid,user->pw_gid,user->pw_gecos,user->pw_ Dir,user->pw_shell); } }
Perform	Root:0:0:root:/root:/bin/bash Bin:1:1:bin:/bin: Daemon:2:2:daemon:/sbin: Adm:3:4:adm:/var/adm: LP:4:7:LP:/VAR/SPOOL/LPD: Sync:5:0:sync:/sbin:/bin/sync Shutdown:6:0:shutdown:/sbin:/sbin/shutdown Halt:7:0:halt:/sbin:/sbin/halt Mail:8:12:mail:/var/spool/mail: News:9:13:news:var/spool/news