1.\" Copyright (c) 1992, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 4. Neither the name of the University nor the names of its contributors 13.\" may be used to endorse or promote products derived from this software 14.\" without specific prior written permission. 15.\" 16.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 17.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 20.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26.\" SUCH DAMAGE. 27.\" 28.\" @(#)zopen.3 8.1 (Berkeley) 6/9/93 29.\" $FreeBSD$ 30.\" 31.Dd June 9, 1993 32.Dt ZOPEN 3 33.Os 34.Sh NAME 35.Nm zopen 36.Nd compressed stream open function 37.Sh SYNOPSIS 38.Fd #include \&"zopen.h\&" 39.Ft FILE * 40.Fn zopen "const char *path" "const char *mode" "int bits" 41.Sh DESCRIPTION 42The 43.Fn zopen 44function 45opens the compressed file whose name is the string pointed to by 46.Fa path 47and associates a stream with it. 48.Pp 49The argument 50.Fa mode 51points to one of the following one-character strings: 52.Bl -tag -width indent 53.It Dq Li r 54Open compressed file for reading. 55The stream is positioned at the beginning of the file. 56.It Dq Li w 57Truncate file to zero length or create compressed file for writing. 58The stream is positioned at the beginning of the file. 59.El 60.Pp 61Any created files will have mode 62.Pf \\*q Dv S_IRUSR 63\&| 64.Dv S_IWUSR 65\&| 66.Dv S_IRGRP 67\&| 68.Dv S_IWGRP 69\&| 70.Dv S_IROTH 71\&| 72.Dv S_IWOTH Ns \\*q 73.Pq Li 0666 , 74as modified by the process' 75umask value (see 76.Xr umask 2 ) . 77.Pp 78Files may only be read or written. 79Seek operations are not allowed. 80.Pp 81The 82.Fa bits 83argument, if non-zero, is set to the bits code limit. 84If zero, the default is 16. 85See 86.Xr compress 1 87for more information. 88.Sh RETURN VALUES 89Upon successful completion 90.Fn zopen 91returns a 92.Tn FILE 93pointer. 94Otherwise, 95.Dv NULL 96is returned and the global variable 97.Va errno 98is set to indicate the error. 99.Sh ERRORS 100.Bl -tag -width [EINVAL] 101.It Bq Er EINVAL 102The 103.Fa mode 104or 105.Fa bits 106arguments specified to 107.Fn zopen 108were invalid. 109.It Bq Er EFTYPE 110The compressed file starts with an invalid header, or the compressed 111file is compressed with more bits than can be handled. 112.El 113.Pp 114The 115.Fn zopen 116function may also fail and set 117.Va errno 118for any of the errors specified for the routines 119.Xr fopen 3 120or 121.Xr funopen 3 . 122.Sh SEE ALSO 123.Xr compress 1 , 124.Xr fopen 3 , 125.Xr funopen 3 126.Sh HISTORY 127The 128.Nm 129function 130first appeared in 131.Bx 4.4 . 132.Sh BUGS 133The 134.Fn zopen 135function 136may not be portable to systems other than 137.Bx . 138