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.\" $Id$
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.Dd August 24, 2016
.Os
.Dt ELFTC_TIMESTAMP 3
.Sh NAME
.Nm elftc_timestamp
.Nd return the current or environment-provided timestamp
.Sh LIBRARY
.Lb libelftc
.Sh SYNOPSIS
.In libelftc.h
.Ft int
.Fo elftc_timestamp
.Fa "time_t *timestamp"
.Fc
.Sh DESCRIPTION
The
.Fn elftc_timestamp
function returns a timestamp supplied by the
.Ev SOURCE_DATE_EPOCH
environment variable, or the current time provided by
.Xr time 3
if the environment variable is not set.
.Pp
The
.Ar timestamp
argument specifies a pointer to the location where the timestamp will be
stored.
.Sh RETURN VALUE
Function
.Fn elftc_timestamp
returns 0 on success, and -1 in the event of an error.
.Sh ERRORS
The
.Fn elftc_timestamp
function may fail with the following errors:
.Bl -tag -width ".Bq Er ERANGE"
.It Bq Er EINVAL
.Ev SOURCE_DATE_EPOCH
contains invalid characters.
.It Bq Er ERANGE
.Ev SOURCE_DATE_EPOCH
specifies a negative value or a value that cannot be stored in a
time_t.
.El
The
.Fn elftc_timestamp
function may also fail for any of the reasons described in
.Xr strtoll 3 .
.Sh SEE ALSO
.Xr strtoll 3 ,
.Xr time 3