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stdin -> stdout

hi.

i was wondering, what's the simplest way to echo the standard input to
the standard output, with no modification.

i came up with:

....
while True:
try:
raw_input()
except EOFError:
break
....

but i guess there must be a simpler way.

using bash i simply do 'cat', *sigh*!

bye

max

ps: in perl you ca do this:

....
while ($line = <STDIN>)
{
print STDOUT ("$line");
}
....
Aug 19 '05 #1
8 2381
2005/8/19, max(01)* <ma**@fisso.cas a>:
hi.

i was wondering, what's the simplest way to echo the standard input to
the standard output, with no modification.

i came up with:

...
while True:
try:
raw_input()
except EOFError:
break
...

but i guess there must be a simpler way.

using bash i simply do 'cat', *sigh*!

bye

max

ps: in perl you ca do this:

...
while ($line = <STDIN>)
{
print STDOUT ("$line");
}
...


Try this.

import sys

line = sys.stdin.readl ine()
while line:
sys.stdout.writ e(line)
line = sys.stdin.readl ine()

--
I like python!
My Donews Blog: http://www.donews.net/limodou
Aug 19 '05 #2
On Fri, 19 Aug 2005 15:26:27 GMT,
"max(01)*" <ma**@fisso.cas a> wrote:
ps: in perl you ca do this: ...
while ($line = <STDIN>)
{
print STDOUT ("$line");
}
...


import fileinput
import sys

for line in fileinput.input ():
sys.stdout.writ e(line)

Regards,
Dan

--
Dan Sommers
<http://www.tombstoneze ro.net/dan/>
Aug 19 '05 #3
gry
import sys
for l in sys.stdin:
sys.stdout.writ e(l)

-- George

Aug 19 '05 #4
max(01)* wrote:
i was wondering, what's the simplest way to echo the standard input to
the standard output, with no modification.


import sys
for line in iter(sys.stdin. readline, ''):
sys.stdout.writ e(line)

Note that this uses the second form of iter(), which calls its first
argument repeatedly until it returns the sentinel value (its second
argument).

STeVe
Aug 19 '05 #5
gr*@ll.mit.edu wrote:
import sys
for l in sys.stdin:
sys.stdout.writ e(l)


This is fine if you don't need the reads and writes of lines to run in
lockstep. File iterators read into a buffer, so you'll probably read
4096 bytes from stdin before you ever write a line to stdout. If that's
okay, this is a good solution. OTOH, if you want the reads and writes
to run in lockstep, you should probably use this idiom:

import sys
for line in iter(sys.stdin. readline, ''):
sys.stdout.writ e(line)

STeVe

P.S. You may also be able to get your version working using the -u
(unbuffered) option to Python, but I couldn't.
Aug 19 '05 #6
limodou wrote:
2005/8/19, max(01)* <ma**@fisso.cas a>:
hi.

i was wondering, what's the simplest way to echo the standard input to
the standard output, with no modification.

i came up with:

...
while True:
try:
raw_input()
except EOFError:
break
...

but i guess there must be a simpler way.

using bash i simply do 'cat', *sigh*!

bye

max

ps: in perl you ca do this:

...
while ($line = <STDIN>)
{
print STDOUT ("$line");
}
...

Try this.

import sys

line = sys.stdin.readl ine()
while line:
sys.stdout.writ e(line)
line = sys.stdin.readl ine()


Try this:

import sys
for line in sys.stdin:
sys.stdout.writ e(line)

Aug 19 '05 #7
On Fri, 19 Aug 2005 15:26:27 GMT, max(01)* <ma**@fisso.cas a> wrote:
hi.

i was wondering, what's the simplest way to echo the standard input to
the standard output, with no modification.

i came up with: .... but i guess there must be a simpler way.

using bash i simply do 'cat', *sigh*! .... ps: in perl you ca do this:

...
while ($line = <STDIN>)
{
print STDOUT ("$line");
}
...


Actually, in perl it's easier than that, if you can tolerate that it also
filters file(s) given on the command-line:

while(<>) {
print;
}

or even:

#!/usr/bin/perl -p
;

Of course, not every programming language needs to have easy-to-use
filtering capabilities at the core.

/Jorgen

--
// Jorgen Grahn <jgrahn@ Ph'nglui mglw'nafh Cthulhu
\X/ algonet.se> R'lyeh wgah'nagl fhtagn!
Aug 20 '05 #8
max(01)* wrote:
i was wondering, what's the simplest way to echo the standard input to
the standard output, with no modification. .... ps: in perl you ca do this:

...
while ($line = <STDIN>)
{
print STDOUT ("$line");
}
...


I guess you could, but there wouldn't be much point. In Perl, you can
do this with just command-line flags:

perl -pe '' input.txt

Or if you really want something to put in a file:

print <>

Here's the closest thing I could come up with in Python:

import sys
for line in sys.stdin:
print line,
Aug 20 '05 #9

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