4.2BSD/usr/man/man1/whoami.1

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.TH WHOAMI 1 "24 February 1979"
.UC
.SH NAME
whoami \- print effective current user id
.SH SYNOPSIS
.B whoami
.SH DESCRIPTION
.I Whoami
prints who you are.
It works even if you are su'd, while `who am i' does not since
it uses /etc/utmp.
.SH FILES
.DT
/etc/passwd	Name data base
.SH "SEE ALSO"
who (1)