Tcl Built-In Commands
NAME
read - Read from a channel
SYNOPSIS
read ?-nonewline? channelId
read channelId numBytes
DESCRIPTION
In the first form, the read command reads all of the data from
channelId up to the end of the file.
If the -nonewline switch is specified then the last character
of the file is discarded if it is a newline.
In the second form, the extra argument specifies how many bytes to
read. Exactly that many bytes will be read and returned, unless
there are fewer than numBytes left in the file; in this case
all the remaining bytes are returned.
If channelId is in nonblocking mode, the command may not read
as many bytes as requested: once all available input has been read,
the command will return the data that is available rather than blocking
for more input.
The -nonewline switch is ignored if the command returns
before reaching the end of the file.
Read translates end-of-line sequences in the input into
newline characters according to the -translation option
for the channel.
See the manual entry for fconfigure for details on the
-translation option.
SEE ALSO
eof(n), fblocked(n), fconfigure(n)
KEYWORDS
blocking, channel, end of line, end of file, nonblocking, read, translation
Last change: 7.5
[ tcl8.0a1 | tk8.0a1 | X-ref ]
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