What does the \x1a characters mean

Question

What does the \x1a character mean and why does mysql_real_escape_string escape it?

From the documentation:

mysql_real_escape_string() calls MySQL's library function mysql_real_escape_string, which prepends backslashes to the following characters: \x00, \n, \r, \, ', " and \x1a.

A ASCII Characters reference describes it as Substitute character, but this doesn't say much.

I believe `1A` is `Ctrl + Z` which is commonly used for EOF. — Brad, Apr 27 '13 at 18:39

score 13 · Accepted Answer · edited Nov 09 '20 at 05:26

13

It's a Unicode escape sequence, in hexadecimal (base 16). \x1a is the "substitute" character.

See also: https://en.wikipedia.org/wiki/Substitute_character

Why does mysql_real_escape_string escape it?

According to the documentation,

Strictly speaking, MySQL requires only that backslash and the quote character used to quote the string in the query be escaped. mysql_real_escape_string() quotes the other characters to make them easier to read in log files.

edited Nov 09 '20 at 05:26

Mr.Z

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answered Apr 27 '13 at 18:39

Matt Ball

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Why does `mysql_real_escape_string` escape it? – Emanuil Rusev Apr 27 '13 at 18:44

score 12 · Answer 2 · answered Apr 27 '13 at 18:41

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\x1A is CTRL+Z control character. It is also EOF marker.

answered Apr 27 '13 at 18:41

Ziumin

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keeri · Answer 3 · 2013-04-27T18:46:23.493

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\x1a is a SUB control character, used to mark end of a file (EOF).

edited Apr 27 '13 at 18:46

answered Apr 27 '13 at 18:40

keeri

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score 2 · Answer 4 · answered Apr 27 '13 at 18:40

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It is a hexadecimal escape sequence for the SUB character.

answered Apr 27 '13 at 18:40

Niet the Dark Absol

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Why does `mysql_real_escape_string` escape it? – Emanuil Rusev Apr 27 '13 at 18:43
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Because MySQL travels through a network stream, and the EOF character may be interpreted to mean the end of the stream. – Niet the Dark Absol Apr 27 '13 at 18:45
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That's not the reason that the documentation cites. – Matt Ball Apr 27 '13 at 18:48

score 0 · Answer 5 · answered Apr 29 '18 at 11:10

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This is is because of an empty line et the eof file the program try to read the values in the empty line and read \x1a

answered Apr 29 '18 at 11:10

Nelu

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What does the \x1a characters mean

5 Answers5

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