gen/FreeBSD/gethostname.3

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  32 .\"     @(#)gethostname.3       8.1 (Berkeley) 6/4/93
  33 .\" $FreeBSD: src/lib/libc/gen/gethostname.3,v 1.13 2002/12/19 09:40:21 ru Exp $
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  35 .Dd June 4, 1993
  36 .Dt GETHOSTNAME 3
  37 .Os
  38 .Sh NAME
  39 .Nm gethostname ,
  40 .Nm sethostname
  41 .Nd get/set name of current host
  42 .Sh LIBRARY
  43 .Lb libc
  44 .Sh SYNOPSIS
  45 .In unistd.h
  46 .Ft int
  47 .Fn gethostname "char *name" "int namelen"
  48 .Ft int
  49 .Fn sethostname "const char *name" "int namelen"
  50 .Sh DESCRIPTION
  51 The
  52 .Fn gethostname
  53 function
  54 returns the standard host name for the current processor, as
  55 previously set by
  56 .Fn sethostname .
  57 The
  58 .Fa namelen
  59 argument
  60 specifies the size of the
  61 .Fa name
  62 array.  The returned name is null-terminated unless insufficient
  63 space is provided.
  64 .Pp
  65 The
  66 .Fn sethostname
  67 function
  68 sets the name of the host machine to be
  69 .Fa name ,
  70 which has length
  71 .Fa namelen .
  72 This call is restricted to the super-user and
  73 is normally used only when the system is bootstrapped.
  74 .Sh RETURN VALUES
  75 .Rv -std
  76 .Sh ERRORS
  77 The following errors may be returned by these calls:
  78 .Bl -tag -width Er
  79 .It Bq Er EFAULT
  80 The
  81 .Fa name
  82 or
  83 .Fa namelen
  84 argument gave an
  85 invalid address.
  86 .It Bq Er EPERM
  87 The caller tried to set the hostname and was not the super-user.
  88 .El
  89 .Sh SEE ALSO
  90 .Xr gethostid 3 ,
  91 .Xr sysctl 3
  92 .Sh BUGS
  93 Host names are limited to
  94 .Dv MAXHOSTNAMELEN
  95 (from
  96 .Ao Pa sys/param.h Ac )
  97 characters, currently 256.
  98 This includes the trailing
  99 .Dv NUL .
 100 .Sh HISTORY
 101 The
 102 .Fn gethostname
 103 function appeared in
 104 .Bx 4.2 .