xref: /titanic_52/usr/src/boot/lib/libz/zopen.3 (revision 4a5d661a82b942b6538acd26209d959ce98b593a)
1.\" Copyright (c) 2014 Xin Li <delphij@FreeBSD.org>
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25.\" $FreeBSD$
26.\"
27.Dd March 5, 2014
28.Dt ZOPEN 3
29.Os
30.Sh NAME
31.Nm zopen
32.Nd open a gzip compressed stream
33.Sh LIBRARY
34.Lb libz
35.Sh SYNOPSIS
36.Ft FILE *
37.Fn zopen "const char *path" "const char *mode"
38.Sh DESCRIPTION
39The
40.Fn zopen
41opens a gzip file whose name is the string pointed to by
42.Fa path
43and associates a stream with it.
44It is a wrapper around
45.Xr zlib 3
46and standard stream I/O APIs.
47.Pp
48The argument
49.Fa mode
50have the same meaning as it does in
51.Xr fopen 3 .
52.Pp
53The
54.Nm
55function will associate read, write, seek and close
56functions of
57.Xr zlib 3
58after successfully opened a file with
59.Xr funopen 3
60so that they will be used to read or write the new stream.
61.Sh RETURN VALUES
62Upon successful completion
63.Nm
64returns a
65.Tn FILE
66pointer.
67Otherwise,
68.Dv NULL
69is returned and the global variable
70.Va errno
71is set to indicate the error.
72.Sh ERRORS
73In addition to the errors documented for
74.Xr fopen 3 ,
75the
76.Nm
77function may also fail for:
78.Bl -tag -width Er
79.It Bq Er ENOMEM
80Insufficient memory is available.
81.El
82.Sh COMPATIBILITY
83This implementation of
84.Nm
85function first appeared in
86.Nx 1.6
87and
88.Fx 4.5 .
89The
90.Nm
91function may not be portable to systems other than
92.Fx .
93.Sh SEE ALSO
94.Xr fopen 3 ,
95.Xr funopen 3 ,
96.Xr zlib 3
97