python equivalent for fputc

[Putty]

I'm porting a program a friend wrote in C over to Python and I've run
into a little hang-up. The C program writes characters out to a file.
I'm 99% sure that a conversion is going on here as well. I know for a
fact that it's taking a number and turning it into a character.

So what kind of call can I make to do it in Python?

[bearophileHUGS]

Putty wrote:

I'm porting a program a friend wrote in C over to Python and I've run
into a little hang-up. The C program writes characters out to a file.
I'm 99% sure that a conversion is going on here as well. I know for a
fact that it's taking a number and turning it into a character.
So what kind of call can I make to do it in Python?

There may be some ways. Here is the data:
from random import randint
vals = [randint(0, 255) for i in xrange(10)]

This is probably the most common way:
print "".join(chr(c) for c in vals)

If you need to access the chars one after the other, this may be a
(quite slower, but less memory consuming) alternative:

import sys
write = sys.stdout.write
for c in vals:
write(chr(c))
print

In some cases a solution like this one can be useful too:

import array
print array.array("B", vals).tostring()

Bye,
bearophile

[John Machin]

Putty wrote:

I'm porting a program a friend wrote in C over to Python and I've run
into a little hang-up. The C program writes characters out to a file.
I'm 99% sure that a conversion is going on here as well. I know for a
fact that it's taking a number and turning it into a character.

C is a low-level language -- a character *is* a number :-)

>
So what kind of call can I make to do it in Python?

*Guessing* that you mean e.g. fputc(97, f) writes the character 'a' to
the file whose handle is f ...

In Python the more-or-less literal translation (ignoring the fputc
return value) would be f.write(chr(97))

Note:
|>>ord('a')
97
|>>chr(97)
'a'

HTH -- if not, show us (relevant parts of) the actual source that you
are porting.

Cheers,
John

[Putty]

Thanks, John. That's exactly what I was looking for!

John Machin wrote:

Putty wrote:

I'm porting a program a friend wrote in C over to Python and I've run
into a little hang-up. The C program writes characters out to a file.
I'm 99% sure that a conversion is going on here as well. I know for a
fact that it's taking a number and turning it into a character.

C is a low-level language -- a character *is* a number :-)

So what kind of call can I make to do it in Python?

*Guessing* that you mean e.g. fputc(97, f) writes the character 'a' to
the file whose handle is f ...

In Python the more-or-less literal translation (ignoring the fputc
return value) would be f.write(chr(97))

Note:
|>>ord('a')
97
|>>chr(97)
'a'

HTH -- if not, show us (relevant parts of) the actual source that you
are porting.

Cheers,
John

[Fredrik Lundh]

Putty wrote:

I'm porting a program a friend wrote in C over to Python and I've run
into a little hang-up. The C program writes characters out to a file.
I'm 99% sure that a conversion is going on here as well. I know for a
fact that it's taking a number and turning it into a character.

that's what fputc does, of course -- it takes an integer and writes
it as a character to the given stream.

f = fopen(filename, "w");
fputc(c, f);
fclose(f)

becomes

f = open(filename, "w")
f.write(chr(value))
f.close()

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