.\" Hey Emacs! This file is -*- nroff -*- source. .\" .\" Copyright © 2002 - Philip Howard - All rights reserved .\" .\" This program is free software; you can redistribute it and/or .\" modify it under the terms of the GNU Lesser General Public .\" License as published by the Free Software Foundation; either .\" version 2.1 of the License, or (at your option) any later version. .\" .\" This library is distributed in the hope that it will be useful, .\" but WITHOUT ANY WARRANTY; without even the implied warranty of .\" MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU .\" Lesser General Public License for more details. .\" .\" You should have received a copy of the GNU Lesser General Public .\" License along with this library; if not, write to the Free Software .\" Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA .\" .TH vrb_get_min 3 2002-09-30 vrb "VRB Programmer's Manual" .SH NAME vrb_get_min - get minimum data from a VRB .SH LIBRARY .B -lvrb .SH SYNOPSIS .B #include .sp .IB "size_t " "vrb_get_min" "(vrb_p " "vrb" ", char *" "target" ", size_t " "minsize" ", size_t " "maxsize" ");" .SH DESCRIPTION .B vrb_get_min Get data from a virtual ring buffer and copy it to the space provider by the caller only if the minimum specified amount can be copied. If less data than the minimum is available, then no data is copied. .SH ARGUMENTS .IB "vrb_p " vrb .br specifies which virtual ring buffer. .sp .IB "char *" target .br specifies the location where to copy the data to. .sp .IB "size_t " minsize .br specifies the minimum length of data that must be available to be copied. .sp .IB "size_t " maxsize .br specifies the maximum length of data that can be obtained from the virtual ring buffer. .SH "RETURN VALUE" .I size_t .br The actual length of data copied is returned, which can be any value from the minimum size to the maximum size, or 0. .SH ERRORS If an error is returned, then .I errno will have the following value: .TP .B EINVAL An invalid virtual ring buffer pointer was specified, or the minimum request exceeds the buffer capacity and thus can never be satisfied. .SH "SEE ALSO" .BR vrb (3), .BR vrb_capacity (3), .BR vrb_data_len (3), .BR vrb_data_ptr (3), .BR vrb_destroy (3), .BR vrb_get (3), .BR vrb_give (3), .BR vrb_init (3), .BR vrb_init_opt (3), .BR vrb_is_empty (3), .BR vrb_is_full (3), .BR vrb_is_not_empty (3), .BR vrb_is_not_full (3), .BR vrb_move (3), .BR vrb_new (3), .BR vrb_new_opt (3), .BR vrb_put (3), .BR vrb_put_all (3), .BR vrb_read (3), .BR vrb_read_min (3), .BR vrb_resize (3), .BR vrb_space_len (3), .BR vrb_space_ptr (3), .BR vrb_take (3), .BR vrb_uninit (3), .BR vrb_write (3), .BR vrb_write_min (3)