cat the file and put it in variables

Hi
I am new to Tcl. I need to do very simple stuff. Cat a file that has
100 lines and every line has two fields. I need to cat the file one
line at a time, and take the value of the fields in two varaibles. Do
some processing and then when file hits EOF quit.


Any comments will be appreciated.

Thanks
Nitin

to simple
1.open the file                    set file [ open filename r ]
2.read the whole file            set str [read $file]
3.split str with "\n" or "\r" newline character
4.foeach loop will help you to access whole line ( that has 2 elements
)

Abhishek

abhishekkabra@gmail.com wrote:
# to simple
# 1.open the file                    set file [ open filename r ]

1.5. fconfigure $file -translation (whatever)

# 2.read the whole file            set str [read $file]
# 3.split str with "\n" or "\r" newline character
# 4.foeach loop will help you to access whole line ( that has 2 elements

The translation option can be used to convert \r, \n, or \r\n into \n during
all input and output operations.

--
SM Ryan http://www.rawbw.com/~wyrmwif/
I'm not even supposed to be here today.

Nitin wrote:
> I am new to Tcl. I need to do very simple stuff. Cat a file that has
> 100 lines and every line has two fields. I need to cat the file one
> line at a time, and take the value of the fields in two varaibles. Do
> some processing and then when file hits EOF quit.

This feels a little bit like homework, so I won't give a full solution.
I'll just point to the pieces you need.

To read the file in, you'll want [open], [read] and [close]. Then you'll
want to [split] the data by newlines (100 lines is a small file) and
iterate over the list of lines using [foreach]. You will probably want
to parse each line with [split] or [regexp] (choosing which to use
depends on the detailed format of the data being read).

Alternatively, you could use [open], [while], [eof], [gets], parse the
line that you've read (see notes above) and put [close] after the loop.

You might or might not find helpful examples by looking on our wiki,
which is nicely indexed by google BTW. ;-)

Donal.

Donal K. Fellows wrote:
>
> Alternatively, you could use [open], [while], [eof], [gets], parse the
> line that you've read (see notes above) and put [close] after the loop.

This is the fastest option of the two :^)

Khaled

In article <1118049979.883757.307600@o13g2000cwo.googlegroups.com>,
Khaled <nospam.ksubs@free.fr> wrote:
>
>
>Donal K. Fellows wrote: 
>
>This is the fastest option of the two :^)
>
>Khaled
>

Not always.  It depends on specifics of the execution environment
and data.

In article <11a7su22bqpjheb@corp.supernews.com>,
SM Ryan  <wyrmwif@tango-sierra-oscar-foxtrot-tango.fake.org> wrote:
>abhishekkabra@gmail.com wrote:
># to simple
># 1.open the file                    set file [ open filename r ]
>
>1.5. fconfigure $file -translation (whatever)
>
># 2.read the whole file            set str [read $file]
># 3.split str with "\n" or "\r" newline character
># 4.foeach loop will help you to access whole line ( that has 2 elements
>
>The translation option can be used to convert \r, \n, or \r\n into \n durin
g
>all input and output operations.

On Mon, 6 Jun 2005, Cameron Laird wrote:

> Indeed it can--but to what purpose that bears on the original requirements
?
>
> I'm tempted to submit
>
>      # *This* certainly is fragile in the face of exceptions.
>  foreach {first second} [split [exec cat $filename] \n] {
>      puts "The two items are '$first' and '$second'."
>  }
>

My first reaction would be:

set fp [open $filename]
while {[gets $fp line] != -1} {
foreach {first second} $line break
# do whatever
}
close $fp

or, as a pure-Tcl alternative to [exec cat]:

package require fileutil
foreach {first second} [split [fileutil::cat $filename] \n] {
# do whatever
}

Michael