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. 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.Dd June 9, 1993 29.Dt ZOPEN 3 30.Os 31.Sh NAME 32.Nm zopen 33.Nd compressed stream open function 34.Sh SYNOPSIS 35.Fd #include \&"zopen.h\&" 36.Ft FILE * 37.Fn zopen "const char *path" "const char *mode" "int bits" 38.Sh DESCRIPTION 39The 40.Fn zopen 41function 42opens the compressed file whose name is the string pointed to by 43.Fa path 44and associates a stream with it. 45.Pp 46The argument 47.Fa mode 48points to one of the following one-character strings: 49.Bl -tag -width indent 50.It Dq Li r 51Open compressed file for reading. 52The stream is positioned at the beginning of the file. 53.It Dq Li w 54Truncate file to zero length or create compressed file for writing. 55The stream is positioned at the beginning of the file. 56.El 57.Pp 58Any created files will have mode 59.Pf \\*q Dv S_IRUSR 60\&| 61.Dv S_IWUSR 62\&| 63.Dv S_IRGRP 64\&| 65.Dv S_IWGRP 66\&| 67.Dv S_IROTH 68\&| 69.Dv S_IWOTH Ns \\*q 70.Pq Li 0666 , 71as modified by the process' 72umask value (see 73.Xr umask 2 ) . 74.Pp 75Files may only be read or written. 76Seek operations are not allowed. 77.Pp 78The 79.Fa bits 80argument, if non-zero, is set to the bits code limit. 81If zero, the default is 16. 82See 83.Xr compress 1 84for more information. 85.Sh RETURN VALUES 86Upon successful completion 87.Fn zopen 88returns a 89.Tn FILE 90pointer. 91Otherwise, 92.Dv NULL 93is returned and the global variable 94.Va errno 95is set to indicate the error. 96.Sh ERRORS 97.Bl -tag -width [EINVAL] 98.It Bq Er EINVAL 99The 100.Fa mode 101or 102.Fa bits 103arguments specified to 104.Fn zopen 105were invalid. 106.It Bq Er EFTYPE 107The compressed file starts with an invalid header, or the compressed 108file is compressed with more bits than can be handled. 109.El 110.Pp 111The 112.Fn zopen 113function may also fail and set 114.Va errno 115for any of the errors specified for the routines 116.Xr fopen 3 117or 118.Xr funopen 3 . 119.Sh SEE ALSO 120.Xr compress 1 , 121.Xr fopen 3 , 122.Xr funopen 3 123.Sh HISTORY 124The 125.Nm 126function 127first appeared in 128.Bx 4.4 . 129.Sh BUGS 130The 131.Fn zopen 132function 133may not be portable to systems other than 134.Bx . 135