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.\" 3. All advertising materials mentioning features or use of this software 13.\" must display the following acknowledgement: 14.\" This product includes software developed by the University of 15.\" California, Berkeley and its contributors. 16.\" 4. Neither the name of the University nor the names of its contributors 17.\" may be used to endorse or promote products derived from this software 18.\" without specific prior written permission. 19.\" 20.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30.\" SUCH DAMAGE. 31.\" 32.\" @(#)zopen.3 8.1 (Berkeley) 6/9/93 33.\" $FreeBSD$ 34.\" 35.Dd June 9, 1993 36.Dt ZOPEN 3 37.Os 38.Sh NAME 39.Nm zopen 40.Nd compressed stream open function 41.Sh SYNOPSIS 42.Fd #include \&"zopen.h\&" 43.Ft FILE * 44.Fn zopen "const char *path" "const char *mode" "int bits" 45.Sh DESCRIPTION 46The 47.Fn zopen 48function 49opens the compressed file whose name is the string pointed to by 50.Fa path 51and associates a stream with it. 52.Pp 53The argument 54.Fa mode 55points to one of the following one-character strings: 56.Bl -tag -width indent 57.It Dq Li r 58Open compressed file for reading. 59The stream is positioned at the beginning of the file. 60.It Dq Li w 61Truncate file to zero length or create compressed file for writing. 62The stream is positioned at the beginning of the file. 63.El 64.Pp 65Any created files will have mode 66.Pf \\*q Dv S_IRUSR 67\&| 68.Dv S_IWUSR 69\&| 70.Dv S_IRGRP 71\&| 72.Dv S_IWGRP 73\&| 74.Dv S_IROTH 75\&| 76.Dv S_IWOTH Ns \\*q 77.Pq Li 0666 , 78as modified by the process' 79umask value (see 80.Xr umask 2 ) . 81.Pp 82Files may only be read or written. 83Seek operations are not allowed. 84.Pp 85The 86.Fa bits 87argument, if non-zero, is set to the bits code limit. 88If zero, the default is 16. 89See 90.Xr compress 1 91for more information. 92.Sh RETURN VALUES 93Upon successful completion 94.Fn zopen 95returns a 96.Tn FILE 97pointer. 98Otherwise, 99.Dv NULL 100is returned and the global variable 101.Va errno 102is set to indicate the error. 103.Sh ERRORS 104.Bl -tag -width [EINVAL] 105.It Bq Er EINVAL 106The 107.Fa mode 108or 109.Fa bits 110arguments specified to 111.Fn zopen 112were invalid. 113.It Bq Er EFTYPE 114The compressed file starts with an invalid header, or the compressed 115file is compressed with more bits than can be handled. 116.El 117.Pp 118The 119.Fn zopen 120function may also fail and set 121.Va errno 122for any of the errors specified for the routines 123.Xr fopen 3 124or 125.Xr funopen 3 . 126.Sh SEE ALSO 127.Xr compress 1 , 128.Xr fopen 3 , 129.Xr funopen 3 130.Sh HISTORY 131The 132.Nm 133function 134first appeared in 135.Bx 4.4 . 136.Sh BUGS 137The 138.Fn zopen 139function 140may not be portable to systems other than 141.Bx . 142