ZOPEN(3) BSD Library Functions Manual ZOPEN(3)

NAME
     zzooppeenn - compressed stream open function

SYNOPSIS
     ##iinncclluuddee ""zzooppeenn..hh""

     FILE *
     zzooppeenn(const char *path, const char *mode, int bits);

DESCRIPTION
     The zzooppeenn() function opens the compressed file whose name is the string
     pointed to by path and associates a stream with it.

     The argument mode points to one of the following one-character strings:

     ``r''   Open compressed file for reading.  The stream is positioned at
             the beginning of the file.

     ``w''   Truncate file to zero length or create compressed file for writ-
             ing.  The stream is positioned at the beginning of the file.

     Any created files will have mode "SIRUSR | SIWUSR | SIRGRP | SIWGRP |
     SIROTH | SIWOTH" (0666), as modified by the process' umask value (see
     umask(2)).

     Files may only be read or written.  Seek operations are not allowed.

     The bits argument, if non-zero, is set to the bits code limit.  If zero,
     the default is 16.  See compress(1) for more information.

RETURN VALUES
     Upon successful completion zzooppeenn() returns a FILE pointer.  Otherwise,
     NULL is returned and the global variable errno is set to indicate the
     error.

EERRRROORRSS
     [EINVAL]  The mode or bits arguments specified to zzooppeenn() were invalid.

     [EFTYPE]  The compressed file starts with an invalid header, or the com-
               pressed file is compressed with more bits than can be handled.

     The zzooppeenn() function may also fail and set errno for any of the errors
     specified for the routines fopen(3) or funopen(3).

SEE ALSO
     compress(1), fopen(3), funopen(3)

HISTORY     The zzooppeenn function first appeared in 4.4BSD.

BUGS
     The zzooppeenn() function may not be portable to systems other than BSD.

BSD                              June 9, 1993                              BSD