1.\" Copyright (c) 2010 Ed Schouten <ed@FreeBSD.org> 2.\" All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 13.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 14.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 16.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 17.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 18.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 19.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 20.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 21.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 22.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 23.\" SUCH DAMAGE. 24.\" 25.\" $FreeBSD$ 26.\" 27.Dd October 27, 2011 28.Dt GETUTXENT 3 29.Os 30.Sh NAME 31.Nm endutxent , 32.Nm getutxent , 33.Nm getutxid , 34.Nm getutxline , 35.Nm getutxuser , 36.Nm pututxline , 37.Nm setutxdb , 38.Nm setutxent 39.Nd user accounting database functions 40.Sh LIBRARY 41.Lb libc 42.Sh SYNOPSIS 43.In utmpx.h 44.Ft void 45.Fn endutxent "void" 46.Ft struct utmpx * 47.Fn getutxent "void" 48.Ft struct utmpx * 49.Fn getutxid "const struct utmpx *id" 50.Ft struct utmpx * 51.Fn getutxline "const struct utmpx *line" 52.Ft struct utmpx * 53.Fn getutxuser "const char *user" 54.Ft struct utmpx * 55.Fn pututxline "const struct utmpx *utmpx" 56.Ft int 57.Fn setutxdb "int type" "const char *file" 58.Ft void 59.Fn setutxent "void" 60.Sh DESCRIPTION 61These functions operate on the user accounting database which stores 62records of various system activities, such as user login and logouts, 63but also system startups and shutdowns and modifications to the system's 64clock. 65The system stores these records in three databases, each having a 66different purpose: 67.Bl -tag -width indent 68.It Pa /var/run/utx.active 69Log of currently active user login sessions. 70This file is similar to the traditional 71.Pa utmp 72file. 73This file only contains process related entries, such as user login and 74logout records. 75.It Pa /var/log/utx.lastlogin 76Log of last user login entries per user. 77This file is similar to the traditional 78.Pa lastlog 79file. 80This file only contains user login records for users who have at least 81logged in once. 82.It Pa /var/log/utx.log 83Log of all entries, sorted by date of addition. 84This file is similar to the traditional 85.Pa wtmp 86file. 87This file may contain any type of record described below. 88.El 89.Pp 90Each entry in these databases is defined by the structure 91.Vt utmpx 92found in the include file 93.In utmpx.h : 94.Bd -literal -offset indent 95struct utmpx { 96 short ut_type; /* Type of entry. */ 97 struct timeval ut_tv; /* Time entry was made. */ 98 char ut_id[]; /* Record identifier. */ 99 pid_t ut_pid; /* Process ID. */ 100 char ut_user[]; /* User login name. */ 101 char ut_line[]; /* Device name. */ 102 char ut_host[]; /* Remote hostname. */ 103}; 104.Ed 105.Pp 106The 107.Fa ut_type 108field indicates the type of the log entry, which can have one of the 109following values: 110.Bl -tag -width LOGIN_PROCESS 111.It Dv EMPTY 112No valid user accounting information. 113.It Dv BOOT_TIME 114Identifies time of system boot. 115.It Dv SHUTDOWN_TIME 116Identifies time of system shutdown. 117.It Dv OLD_TIME 118Identifies time when system clock changed. 119.It Dv NEW_TIME 120Identifies time after system clock changed. 121.It Dv USER_PROCESS 122Identifies a process. 123.It Dv INIT_PROCESS 124Identifies a process spawned by the init process. 125.It Dv LOGIN_PROCESS 126Identifies the session leader of a logged-in user. 127.It Dv DEAD_PROCESS 128Identifies a session leader who has exited. 129.El 130.Pp 131Entries of type 132.Dv INIT_PROCESS 133and 134.Dv LOGIN_PROCESS 135are not processed by this implementation. 136.Pp 137Other fields inside the structure are: 138.Bl -tag -width ut_user 139.It Fa ut_tv 140The time the event occurred. 141This field is used for all types of entries, except 142.Dv EMPTY . 143.It Fa ut_id 144An identifier that is used to refer to the entry. 145This identifier can be used to remove or replace a login entry by 146writing a new entry to the database containing the same value for 147.Fa ut_id . 148This field is only applicable to entries of type 149.Dv USER_PROCESS , 150.Dv INIT_PROCESS , 151.Dv LOGIN_PROCESS 152and 153.Dv DEAD_PROCESS . 154.It Fa ut_pid 155The process identifier of the session leader of the login session. 156This field is only applicable to entries of type 157.Dv USER_PROCESS , 158.Dv INIT_PROCESS , 159.Dv LOGIN_PROCESS 160and 161.Dv DEAD_PROCESS . 162.It Fa ut_user 163The user login name corresponding with the login session. 164This field is only applicable to entries of type 165.Dv USER_PROCESS 166and 167.Dv INIT_PROCESS . 168For 169.Dv INIT_PROCESS 170entries this entry typically contains the name of the login process. 171.It Fa ut_line 172The name of the TTY character device, without the leading 173.Pa /dev/ 174prefix, corresponding with the device used to facilitate the user login 175session. 176If no TTY character device is used, this field is left blank. 177This field is only applicable to entries of type 178.Dv USER_PROCESS 179and 180.Dv LOGIN_PROCESS . 181.It Fa ut_host 182The network hostname of the remote system, connecting to perform a user 183login. 184If the user login session is not performed across a network, this field 185is left blank. 186This field is only applicable to entries of type 187.Dv USER_PROCESS . 188.El 189.Pp 190This implementation guarantees all inapplicable fields are discarded. 191The 192.Fa ut_user , 193.Fa ut_line 194and 195.Fa ut_host 196fields of the structure returned by the library functions are also 197guaranteed to be null-terminated in this implementation. 198.Pp 199The 200.Fn getutxent 201function can be used to read the next entry from the user accounting 202database. 203.Pp 204The 205.Fn getutxid 206function searches for the next entry in the database of which the 207behaviour is based on the 208.Fa ut_type 209field of 210.Fa id . 211If 212.Fa ut_type 213has a value of 214.Dv BOOT_TIME , 215.Dv SHUTDOWN_TIME , 216.Dv OLD_TIME 217or 218.Dv NEW_TIME , 219it will return the next entry whose 220.Fa ut_type 221has an equal value. 222If 223.Fa ut_type 224has a value of 225.Dv USER_PROCESS , 226.Dv INIT_PROCESS , 227.Dv LOGIN_PROCESS 228or 229.Dv DEAD_PROCESS , 230it will return the next entry whose 231.Fa ut_type 232has one of the previously mentioned values and whose 233.Fa ut_id 234is equal. 235.Pp 236The 237.Fn getutxline 238function searches for the next entry in the database whose 239.Fa ut_type 240has a value of 241.Dv USER_PROCESS 242or 243.Dv LOGIN_PROCESS 244and whose 245.Fa ut_line 246is equal to the same field in 247.Fa line . 248.Pp 249The 250.Fn getutxuser 251function searches for the next entry in the database whose 252.Fa ut_type 253has a value of 254.Dv USER_PROCESS 255and whose 256.Fa ut_user 257is equal to 258.Fa user . 259.Pp 260The previously mentioned functions will automatically try to open the 261user accounting database if not already done so. 262The 263.Fn setutxdb 264and 265.Fn setutxent 266functions allow the database to be opened manually, causing the offset 267within the user accounting database to be rewound. 268The 269.Fn endutxent 270function closes the database. 271.Pp 272The 273.Fn setutxent 274database always opens the active sessions database. 275The 276.Fn setutxdb 277function opens the database identified by 278.Fa type , 279whose value is either 280.Dv UTXDB_ACTIVE , 281.Dv UTXDB_LASTLOGIN 282or 283.Dv UTXDB_LOG . 284It will open a custom file with filename 285.Fa file 286instead of the system-default if 287.Fa file 288is not null. 289Care must be taken that when using a custom filename, 290.Fa type 291still has to match with the actual format, since each database may use 292its own file format. 293.Pp 294The 295.Fn pututxline 296function writes record 297.Fa utmpx 298to the system-default user accounting databases. 299The value of 300.Fa ut_type 301determines which databases are modified. 302.Pp 303Entries of type 304.Dv SHUTDOWN_TIME , 305.Dv OLD_TIME 306and 307.Dv NEW_TIME 308will only be written to 309.Pa /var/log/utx.log . 310.Pp 311Entries of type 312.Dv USER_PROCESS 313will also be written to 314.Pa /var/run/utx.active 315and 316.Pa /var/log/utx.lastlogin . 317.Pp 318Entries of type 319.Dv DEAD_PROCESS 320will only be written to 321.Pa /var/log/utx.log 322and 323.Pa /var/run/utx.active 324if a corresponding 325.Dv USER_PROCESS , 326.Dv INIT_PROCESS 327or 328.Dv LOGIN_PROCESS 329entry whose 330.Fa ut_id 331is equal has been found in the latter. 332.Pp 333In addition, entries of type 334.Dv BOOT_TIME 335and 336.Dv SHUTDOWN_TIME 337will cause all existing entries in 338.Pa /var/run/utx.active 339to be discarded. 340.Pp 341All entries whose type has not been mentioned previously, are discarded 342by this implementation of 343.Fn pututxline . 344This implementation also ignores the value of 345.Fa ut_tv . 346.Sh RETURN VALUES 347The 348.Fn getutxent , 349.Fn getutxid , 350.Fn getutxline , 351and 352.Fn getutxuser 353functions return a pointer to an 354.Vt utmpx 355structure that matches the mentioned constraints on success or 356.Dv NULL 357when reaching the end-of-file or when an error occurs. 358.Pp 359The 360.Fn pututxline 361function returns a pointer to an 362.Vt utmpx 363structure containing a copy of the structure written to disk upon 364success. 365It returns 366.Dv NULL 367when the provided 368.Vt utmpx 369is invalid, or 370.Fa ut_type 371has a value of 372.Dv DEAD_PROCESS 373and an entry with an identifier with a value equal to the field 374.Fa ut_id 375was not found; the global variable 376.Va errno 377is set to indicate the error. 378.Pp 379The 380.Fn setutxdb 381function returns 0 if the user accounting database was opened 382successfully. 383Otherwise, -1 is returned and the global variable 384.Va errno 385is set to indicate the error. 386.Sh ERRORS 387In addition to the error conditions described in 388.Xr open 2 , 389.Xr fdopen 3 , 390.Xr fopen 3 , 391.Xr fseek 3 , 392the 393.Fn pututxline 394function can generate the following errors: 395.Bl -tag -width Er 396.It Bq Er ESRCH 397The value of 398.Fa ut_type 399is DEAD_PROCESS, and the process entry could not be found. 400.It Bq Er EINVAL 401The value of 402.Fa ut_type 403is not supported by this implementation. 404.El 405In addition to the error conditions described in 406.Xr fopen 3 , 407the 408.Fn setutxdb 409function can generate the following errors: 410.Bl -tag -width Er 411.It Bq Er EINVAL 412The 413.Fa type 414argument contains a value not supported by this implementation. 415.It Bq Er EFTYPE 416The file format is invalid. 417.El 418.Sh SEE ALSO 419.Xr last 1 , 420.Xr write 1 , 421.Xr getpid 2 , 422.Xr gettimeofday 2 , 423.Xr tty 4 , 424.Xr ac 8 , 425.Xr newsyslog 8 , 426.Xr utx 8 427.Sh STANDARDS 428The 429.Fn endutxent , 430.Fn getutxent , 431.Fn getutxid , 432.Fn getutxline 433and 434.Fn setutxent 435functions are expected to conform to 436.St -p1003.1-2008 . 437.Pp 438The 439.Fn pututxline 440function deviates from the standard by writing its records to multiple 441database files, depending on its 442.Fa ut_type . 443This prevents the need for special utility functions to update the other 444databases, such as the 445.Fn updlastlogx 446and 447.Fn updwtmpx 448functions which are available in other implementations. 449It also tries to replace 450.Dv DEAD_PROCESS 451entries in the active sessions database when storing 452.Dv USER_PROCESS 453entries and no entry with the same value for 454.Fa ut_id 455has been found. 456The standard always requires a new entry to be allocated, which could 457cause an unbounded growth of the database. 458.Pp 459The 460.Fn getutxuser 461and 462.Fn setutxdb 463functions, 464the 465.Fa ut_host 466field of the 467.Vt utmpx 468structure and 469.Dv SHUTDOWN_TIME 470are extensions. 471.Sh HISTORY 472These functions appeared in 473.Fx 9.0 . 474They replaced the 475.In utmp.h 476interface. 477.Sh AUTHORS 478.An \&Ed Schouten Aq Mt ed@FreeBSD.org 479