.Dd 2015-10-08 .Dt ENV 1 .Os sbase .Sh NAME .Nm env .Nd modify the environment, then print it or run a command .Sh SYNOPSIS .Nm .Op Fl i .Oo Fl u Ar var Oc ... .Oo Ar var Ns = Ns Ar value Oc ... .Oo Ar cmd Oo arg ... Oc Oc .Sh DESCRIPTION .Nm unsets each .Ar var , then adds or sets each .Ar ( var , value ) tuple in the environment. .Pp If .Ar cmd is given, it is executed in this new environment; otherwise, the modified environment is printed to stdout. .Sh OPTIONS .Bl -tag -width Ds .It Fl i Completely ignore the existing environment and execute .Ar cmd only with each .Ar ( var , value ) tuple specified. .It Fl u Ar var Unset .Ar var in the environment. .El .Sh SEE ALSO .Xr printenv 1 , .Xr putenv 3 , .Xr environ 7 .Sh STANDARDS The .Nm utility is compliant with the .St -p1003.1-2013 specification. .Pp The .Op Fl u flag is an extension to that specification.