.\" Copyright (c) 2017, Martin Kepplinger <martink@posteo.de>
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.TH TS_ERROR_FN 3  "" "" "tslib"
.SH NAME
ts_error_fn \- use a custom error function for libts library errors
.SH SYNOPSIS
.nf
.B #include <tslib.h>
.sp
.BI "int (*ts_error_fn)(const char *fmt, va_list ap);
.sp
.fi

.SH DESCRIPTION
.BR ts_error_fn ()
is by default implemented similar like this:
.nf

static int errfn(const char *fmt, va_list ap)
{
        return vfprintf(stderr, fmt, ap);
}       

.fi
inside the library. It is exposed to the user and can be replaced by a custom
error function. Simply assign your custom implementation to
.BR ts_error_fn
like
.nf

ts_error_fn = my_custom_errfn;

.fi
It can be used to write the system log files, for example. The ts_print_mt test
program has an example.
.SH RETURN VALUE
user defined.

.SH SEE ALSO
.BR ts_read (3),
.BR ts_open (3),
.BR ts_setup (3),
.BR ts_close (3),
.BR ts.conf (5)