.\" Copyright (c) 1992, 1993 .\" The Regents of the University of California. All rights reserved. .\" .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions .\" are met: .\" 1. Redistributions of source code must retain the above copyright .\" notice, this list of conditions and the following disclaimer. .\" 2. Redistributions in binary form must reproduce the above copyright .\" notice, this list of conditions and the following disclaimer in the .\" documentation and/or other materials provided with the distribution. .\" 4. Neither the name of the University nor the names of its contributors .\" may be used to endorse or promote products derived from this software .\" without specific prior written permission. .\" .\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE .\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF .\" SUCH DAMAGE. .\" .\" @(#)zopen.3 8.1 (Berkeley) 6/9/93 .\" $FreeBSD: src/usr.bin/compress/zopen.3,v 1.9 2010/12/11 08:32:16 joel Exp $ .\" .Dd June 9, 1993 .Dt ZOPEN 3 .Os .Sh NAME .Nm zopen .Nd compressed stream open function .Sh SYNOPSIS .Fd #include \&"zopen.h\&" .Ft FILE * .Fn zopen "const char *path" "const char *mode" "int bits" .Sh DESCRIPTION The .Fn zopen function opens the compressed file whose name is the string pointed to by .Fa path and associates a stream with it. .Pp The argument .Fa mode points to one of the following one-character strings: .Bl -tag -width indent .It Dq Li r Open compressed file for reading. The stream is positioned at the beginning of the file. .It Dq Li w Truncate file to zero length or create compressed file for writing. The stream is positioned at the beginning of the file. .El .Pp Any created files will have mode .Pf \\*q Dv S_IRUSR \&| .Dv S_IWUSR \&| .Dv S_IRGRP \&| .Dv S_IWGRP \&| .Dv S_IROTH \&| .Dv S_IWOTH Ns \\*q .Pq Li 0666 , as modified by the process' umask value (see .Xr umask 2 ) . .Pp Files may only be read or written. Seek operations are not allowed. .Pp The .Fa bits argument, if non-zero, is set to the bits code limit. If zero, the default is 16. See .Xr compress 1 for more information. .Sh RETURN VALUES Upon successful completion .Fn zopen returns a .Tn FILE pointer. Otherwise, .Dv NULL is returned and the global variable .Va errno is set to indicate the error. .Sh ERRORS .Bl -tag -width [EINVAL] .It Bq Er EINVAL The .Fa mode or .Fa bits arguments specified to .Fn zopen were invalid. .It Bq Er EFTYPE The compressed file starts with an invalid header, or the compressed file is compressed with more bits than can be handled. .El .Pp The .Fn zopen function may also fail and set .Va errno for any of the errors specified for the routines .Xr fopen 3 or .Xr funopen 3 . .Sh SEE ALSO .Xr compress 1 , .Xr fopen 3 , .Xr funopen 3 .Sh HISTORY The .Nm function first appeared in .Bx 4.4 . .Sh BUGS The .Fn zopen function may not be portable to systems other than .Bx .