NAME

getuid, getgid, geteuid, getegid − get user and group identity

SYNOPSIS

getuid( )

geteuid( )

getgid( )

getegid( )

DESCRIPTION

Getuid returns the real user ID of the current process, geteuid the effective user ID.  The real user ID identifies the person who is logged in, in contradistinction to the effective user ID, which determines his access permission at the moment.  It is thus useful to programs which operate using the ‘set user ID’ mode, to find out who invoked them. 

Getgid returns the real group ID, getegid the effective group ID. 

SEE ALSO

setuid(2)

ASSEMBLER (PDP-11)

(getuid = 24.) 
sys getuid
(real user ID in r0, effective user ID in r1)

(getgid = 47.) 
sys getgid
(real group ID in r0, effective group ID in r1)

7th Edition