'\"macro stdmacro
.\"
.\" Copyright (c) 2017 Ken McDonell.  All Rights Reserved.
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.TH PMSETPROCESSIDENTITY 3 "PCP" "Performance Co-Pilot"
.SH NAME
\f3pmSetProcessIdentity\f1 \- set process user and group id
.SH "C SYNOPSIS"
.ft 3
#include <pcp/pmapi.h>
.sp
int pmSetProcessIdentity(const char *\fIusername\fP);
.sp
cc ... \-lpcp
.ft 1
.SH DESCRIPTION
.B pmSetProcessIdentity
provides a platform-independent method to set the user id
of a process to that matching
.IR username .
.PP
If possible (when the caller is already running as root)
.B pmSetProcessIdentity
will set the group id of the process to that of the matching
user, e.g. using
.I username
and
.BR getpwnam (3).
.PP
A return value of 0 indicates success, otherwise the return
value is an error code that may be decoded with
.BR pmErrStr (3).
.PP
.BR pmSetProcessIdentity
is most often used in conjunction with
.BR pmGetUsername (3)
at process start up.
.SH SEE ALSO
.BR getpwnam (3),
.BR PMAPI (3),
.BR pmErrStr (3),
.BR pmGetUsername (3),
.BR setgid (3)
and
.BR setuid (3).