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>php_stream_make_seekable</H1
><DIV
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><A
NAME="AEN85770"
></A
><P
> (no version information, might be only in CVS)</P
>php_stream_make_seekable -- Convert a stream into a stream is seekable</DIV
><DIV
CLASS="refsect1"
><A
NAME="AEN85773"
></A
><H2
>Description</H2
>int <B
CLASS="methodname"
>php_stream_make_seekable</B
> ( php_stream * origstream, php_stream ** newstream, int flags)<BR
></BR
><P
> <B
CLASS="function"
>php_stream_make_seekable()</B
> checks if <TT
CLASS="parameter"
><I
>origstream</I
></TT
> is
seekable. If it is not, it will copy the data into a new temporary stream.
If successful, <TT
CLASS="parameter"
><I
>newstream</I
></TT
> is always set to the stream that is valid to use, even if the original
stream was seekable.
</P
><P
> <TT
CLASS="parameter"
><I
>flags</I
></TT
> allows you to specify your preference for the seekeable stream that is
returned: use <TT
CLASS="constant"
><B
>PHP_STREAM_NO_PREFERENCE</B
></TT
> to use the default seekable stream
(which uses a dynamically expanding memory buffer, but switches to temporary file backed storage
when the stream size becomes large), or use <TT
CLASS="constant"
><B
>PHP_STREAM_PREFER_STDIO</B
></TT
> to
use "regular" temporary file backed storage.
</P
><P
> <DIV
CLASS="table"
><A
NAME="AEN85796"
></A
><P
><B
>Tabla 43-1. <B
CLASS="function"
>php_stream_make_seekable()</B
> return values</B
></P
><TABLE
BORDER="1"
CLASS="CALSTABLE"
><THEAD
><TR
><TH
ALIGN="LEFT"
VALIGN="MIDDLE"
>Value</TH
><TH
ALIGN="LEFT"
VALIGN="MIDDLE"
>Meaning</TH
></TR
></THEAD
><TBODY
><TR
><TD
ALIGN="LEFT"
VALIGN="MIDDLE"
>PHP_STREAM_UNCHANGED</TD
><TD
ALIGN="LEFT"
VALIGN="MIDDLE"
>Original stream was seekable anyway. <TT
CLASS="parameter"
><I
>newstream</I
></TT
> is set to the value
of <TT
CLASS="parameter"
><I
>origstream</I
></TT
>.
</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="MIDDLE"
>PHP_STREAM_RELEASED</TD
><TD
ALIGN="LEFT"
VALIGN="MIDDLE"
>Original stream was not seekable and has been released. <TT
CLASS="parameter"
><I
>newstream</I
></TT
> is set to the
new seekable stream. You should not access <TT
CLASS="parameter"
><I
>origstream</I
></TT
> anymore.
</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="MIDDLE"
>PHP_STREAM_FAILED</TD
><TD
ALIGN="LEFT"
VALIGN="MIDDLE"
>An error occurred while attempting conversion. <TT
CLASS="parameter"
><I
>newstream</I
></TT
> is set to NULL;
<TT
CLASS="parameter"
><I
>origstream</I
></TT
> is still valid.
</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="MIDDLE"
>PHP_STREAM_CRITICAL</TD
><TD
ALIGN="LEFT"
VALIGN="MIDDLE"
>An error occurred while attempting conversion that has left <TT
CLASS="parameter"
><I
>origstream</I
></TT
> in
an indeterminate state. <TT
CLASS="parameter"
><I
>newstream</I
></TT
> is set to NULL and it is highly recommended
that you close <TT
CLASS="parameter"
><I
>origstream</I
></TT
>.
</TD
></TR
></TBODY
></TABLE
></DIV
>
</P
><DIV
CLASS="note"
><BLOCKQUOTE
CLASS="note"
><P
><B
>Nota: </B
>
If you need to seek and write to the stream, it does not make sense to use this function, because the stream
it returns is not guaranteed to be bound to the same resource as the original stream.
</P
></BLOCKQUOTE
></DIV
><DIV
CLASS="note"
><BLOCKQUOTE
CLASS="note"
><P
><B
>Nota: </B
>
If you only need to seek forwards, there is no need to call this function, as the streams API will emulate
forward seeks when the whence parameter is <TT
CLASS="constant"
><B
>SEEK_CUR</B
></TT
>.
</P
></BLOCKQUOTE
></DIV
><DIV
CLASS="note"
><BLOCKQUOTE
CLASS="note"
><P
><B
>Nota: </B
>
If <TT
CLASS="parameter"
><I
>origstream</I
></TT
> is network based, this function will block until the whole contents
have been downloaded.
</P
></BLOCKQUOTE
></DIV
><DIV
CLASS="note"
><BLOCKQUOTE
CLASS="note"
><P
><B
>Nota: </B
>
NEVER call this function with an <TT
CLASS="parameter"
><I
>origstream</I
></TT
> that is reference by a file pointer
in a PHP script! This function may cause the underlying stream to be closed which could cause a crash
when the script next accesses the file pointer!
</P
></BLOCKQUOTE
></DIV
><DIV
CLASS="note"
><BLOCKQUOTE
CLASS="note"
><P
><B
>Nota: </B
>
In many cases, this function can only succeed when <TT
CLASS="parameter"
><I
>origstream</I
></TT
> is a newly opened
stream with no data buffered in the stream layer. For that reason, and because this function is complicated to
use correctly, it is recommended that you use <B
CLASS="function"
>php_stream_open_wrapper()</B
> and pass in
<TT
CLASS="constant"
><B
>PHP_STREAM_MUST_SEEK</B
></TT
> in your options instead of calling this function directly.
</P
></BLOCKQUOTE
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