addcslashes

[Taras_96]

Hi everyone,

>From what I understand in of addcslashes, addcslashes should add a

backslash before every character listed in the character list. I've
done a couple of experiments:

echo bin2hex(addcslashes("a","a")) gives 5c31, as expected ('\'
followed by 'a')

Next, I tried

echo bin2hex(addcslashes("\0","\0")); which gave 5c 30 30 30, which is
a backslash followed by 3 spaces. What's happening here? I would have
thought that the output would be

5c 00 (backslash followed by a null)

Taras

[Taras_96]

Next, I tried

>
echo bin2hex(addcslashes("\0","\0")); which gave 5c 30 30 30, which is
a backslash followed by 3 spaces. What's happening here? I would have
thought that the output would be

5c 00 (backslash followed by a null)

Taras

Meh, I re-read the manual more closely and realised that: "while other
non-alphanumeric characters with ASCII codes lower than 32 and higher
than 126 converted to octal representation."

so 5c 30 30 30 = \ octal representation of 0

or, if the byte x01 was escaped, the result would be

5c 30 30 31 = \001 = \ octal representation of 01

What is the point of converting to an octal representation? Where
would it be used? I've never heard of this being used in the c
language..

Taras

[Kimmo Laine]

"Taras_96" <ta******@gmail.comwrote in message
news:11*********************@s48g2000cws.googlegro ups.com...

Hi everyone,

>>From what I understand in of addcslashes, addcslashes should add a

backslash before every character listed in the character list. I've
done a couple of experiments:

echo bin2hex(addcslashes("a","a")) gives 5c31, as expected ('\'
followed by 'a')

Ascii lowercase 'a' is 0x61, not 0x31. 0x31 is '1'. 0x5c is indeed a
backslash. I got 61 when I tried the line above.

Next, I tried

echo bin2hex(addcslashes("\0","\0")); which gave 5c 30 30 30, which is
a backslash followed by 3 spaces.

0x30 is ascii '0' (zero), not a space (which is 0x20).

What's happening here?

Something quite odd. Since \0 is the string terminating character, it would
seem that it throws the functions a bit off. File a bug report?

[Taras_96]

On Feb 8, 5:26 pm, "Kimmo Laine" <[e-mail]:

"Taras_96" <[e-mail] in message

news:11*********************@s48g2000cws.googlegro ups.com...

Hi everyone,

>From what I understand in of addcslashes, addcslashes should add a

backslash before every character listed in the character list. I've
done a couple of experiments:

echo bin2hex(addcslashes("a","a")) gives 5c31, as expected ('\'
followed by 'a')

Ascii lowercase 'a' is 0x61, not 0x31. 0x31 is '1'. 0x5c is indeed a
backslash. I got 61 when I tried the line above.

Next, I tried

echo bin2hex(addcslashes("\0","\0")); which gave 5c 30 30 30, which is
a backslash followed by 3 spaces.

0x30 is ascii '0' (zero), not a space (which is 0x20).

What's happening here?

Something quite odd. Since \0 is the string terminating character, it would
seem that it throws the functions a bit off. File a bug report?

You're right about my corrections. For some reason I knew that but I
typed in the wrong things! It's not a bug, it's a documented behavoiur
- see my previous post.