diff options
Diffstat (limited to 'doc/zlib.n')
| -rw-r--r-- | doc/zlib.n | 22 |
1 files changed, 14 insertions, 8 deletions
@@ -193,10 +193,18 @@ How hard to compress the data. Must be an integer from 0 (uncompressed) to 9 .TP \fB\-limit\fI readaheadLimit\fR . -The maximum number of bytes ahead to read when decompressing. This defaults to -1, which ensures that data is always decompressed correctly, but may be -increased to improve performance. This is more useful when the channel is -non-blocking. +The maximum number of bytes ahead to read when decompressing. +.RS +.PP +This option has become \fBirrelevant\fR. It was originally introduced +to prevent Tcl from reading beyond the end of a compressed stream in +multi-stream channels to ensure that the data after was left alone for +further reading, at the cost of speed. +.PP +Tcl now automatically returns any bytes it has read beyond the end of +a compressed stream back to the channel, making them appear as unread +to further readers. +.RE .PP Both compressing and decompressing channel transformations add extra configuration options that may be accessed through \fBchan configure\fR. The @@ -238,10 +246,8 @@ off the data stream. \fB\-limit\fI readaheadLimit\fR . This read-write option is used by decompressing channels to control the -maximum number of bytes ahead to read from the underlying data source. This -defaults to 1, which ensures that data is always decompressed correctly, but -may be increased to improve performance. This is more useful when the channel -is non-blocking. +maximum number of bytes ahead to read from the underlying data source. See +above for more information. .RE .SS "STREAMING SUBCOMMAND" .TP |