perl's -t and -B file tests in ruby?

[Wybo Dekker]

Does ruby have file tests like Perl's:

-t : file (mostly STDIN) is attached to a tty
-B : file is binary

 

[ts]

W> Does ruby have file tests like Perl's:
W> -t : file (mostly STDIN) is attached to a tty

uln% ri IO#tty?
---------------------------------------------------------------- IO#tty?
ios.isatty => true or false
ios.tty? => true or false
------------------------------------------------------------------------
Returns +true+ if _ios_ is associated with a terminal device (tty),
+false+ otherwise.

File.new("testfile").isatty #=> false
File.new("/dev/tty").isatty #=> true

uln%

W> -B : file is binary

Define what is a binary file ?



Guy Decoux

 

[Tim Heaney]

W> -B : file is binary

Define what is a binary file ?

In this context, Perl essentially means that the file has a lot of
non-ASCII characters. From the perlfunc man page

-T File is an ASCII text file (heuristic guess).
-B File is a "binary" file (opposite of -T).

and

The "-T" and "-B" switches work as follows. The
first block or so of the file is examined for odd
characters such as strange control codes or char-
acters with the high bit set. If too many strange
characters (>30%) are found, it's a "-B" file,
otherwise it's a "-T" file. Also, any file con-
taining null in the first block is considered a
binary file. If "-T" or "-B" is used on a file-
handle, the current IO buffer is examined rather
than the first block. Both "-T" and "-B" return
true on a null file, or a file at EOF when testing
a filehandle. Because you have to read a file to
do the "-T" test, on most occasions you want to
use a "-f" against the file first, as in "next
unless -f $file && -T $file".

 

[ts]

T> In this context, Perl essentially means that the file has a lot of
T> non-ASCII characters.

Well, this is fine for english but what do you for other languages ?

The author of this P language is an "anglois" and perhaps he can see the
problem


Guy Decoux

 

[ts]

t> The author of this P language is an "anglois" and perhaps he can see the
^^^^^^
he can't
t> problem


sorry,


Guy Decoux

 

[Wybo Dekker]

In this context, Perl essentially means that the file has a lot of
non-ASCII characters. From the perlfunc man page

-T File is an ASCII text file (heuristic guess).
-B File is a "binary" file (opposite of -T).

and

The "-T" and "-B" switches work as follows. The
first block or so of the file is examined for odd
characters such as strange control codes or char-
acters with the high bit set. If too many strange

In Larry Wall's Reference here ^ he adds:
(that don't look like UTF-8)

 

[ts]

W> In Larry Wall's Reference here ^ he adds:
W> (that don't look like UTF-8)

He is definitively an "anglois" : he know only ASCII and UTF-8


Guy Decoux