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@(#)gethostname.3 8.1 (Berkeley) 6/4/93
.Dd September 2, 2015 .Dt GETHOSTNAME 3 .Os .Sh NAME .Nm gethostname , .Nm sethostname .Nd get/set name of current host .Sh LIBRARY .Lb libc .Sh SYNOPSIS n unistd.h .Ft int .Fn gethostname "char *name" "size_t namelen" .Ft int .Fn sethostname "const char *name" "size_t namelen" .Sh DESCRIPTION .Fn gethostname returns the standard host name for the current machine, as previously set by .Fn sethostname . The parameter .Fa namelen specifies the size of the .Fa name array. The returned name is null-terminated unless insufficient space is provided.
p .Fn sethostname sets the name of the host machine to be .Fa name , which has length .Fa namelen . This call is restricted to the super-user and is normally used only when the system is bootstrapped. .Sh RETURN VALUES If the call succeeds a value of 0 is returned. If the call fails, a value of -1 is returned and an error code is placed in the global location .Va errno . .Sh ERRORS If the .Fn gethostname or .Fn sethostname functions fail, they will set .Va errno for any of the errors specified for the routine .Xr sysctl 3 . .Sh SEE ALSO .Xr gethostid 3 , .Xr sysctl 3 , .Xr sysctl 8 .Sh STANDARDS The .Fn gethostname function conforms to .St -xpg4.2 . .Sh HISTORY The .Nm function call appeared in x 4.2 . .Sh BUGS Host names are limited to .Dv MAXHOSTNAMELEN (from .Ao Pa sys/param.h Ac ) characters including null-termination, currently 256.
Indexes created Sun Nov 02 07:10:05 GMT 2025