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Top Forums Shell Programming and Scripting assign multiple rows value to a variable using eval Post 302642099 by black_fender on Thursday 17th of May 2012 02:38:58 AM
Old 05-17-2012
Quote:
Originally Posted by bakunin
This is the culprit. The "eval" sends the line through the evaluation process a second time, but the first time it has already eaten away your quotation and this second time the newline terminates the line. You have to escape the quotation to protect it for the correct evaluation pass to interpret it.

Notice the difference between:

Code:
echo "abc"                # evaluated once, but the "" are missing in the output
echo "\"abc\""            # evaluated once, the inner "" are there, without escaping
eval echo "\"abc\""       # second evaluation ate the second pair of ""
eval echo "\\"abc\\""     # two evaluations need two-time escaped quoations

I hope this helps.

bakunin

Yes, Bakunin. This approach got my problem solved. I had to "save" a second pair of "" for the 2nd evaluation by using \ .

Many thanks!
 

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ADDSLASHES(3)								 1							     ADDSLASHES(3)

addslashes - Quote string with slashes

SYNOPSIS
string addslashes (string $str) DESCRIPTION
Returns a string with backslashes before characters that need to be escaped. These characters are single quote ( '), double quote ( "), backslash ( ) and NUL (the NULL byte). An example use of addslashes(3) is when you're entering data into string that is evaluated by PHP. For example, O'Reilly is stored in $str, you need to escape $str. (e.g. eval("echo '".addslashes($str)."';"); ) To escape database parameters, DBMS specific escape function (e.g. mysqli_real_escape_string(3) for MySQL or pg_escape_literal(3), pg_escape_string(3) for PostgreSQL) should be used for security reasons. DBMSes have differect escape specification for identifiers (e.g. Table name, field name) than parameters. Some DBMS such as PostgreSQL provides identifier escape function, pg_escape_identifier(3), but not all DBMS provides identifier escape API. If this is the case, refer to your database system manual for proper escaping method. If your DBMS doesn't have an escape function and the DBMS uses to escape special chars, you might be able to use this function only when this escape method is adequate for your database. Please note that use of addslashes(3) for database parameter escaping can be cause of security issues on most databases. The PHP directive magic_quotes_gpc was on by default before PHP 5.4, and it essentially ran addslashes(3) on all GET, POST, and COOKIE data. Do not use addslashes(3) on strings that have already been escaped with magic_quotes_gpc as you'll then do double escaping. The func- tion get_magic_quotes_gpc(3) may come in handy for checking this. PARAMETERS
o $str - The string to be escaped. RETURN VALUES
Returns the escaped string. EXAMPLES
Example #1 An addslashes(3) example <?php $str = "Is your name O'Reilly?"; // Outputs: Is your name O'Reilly? echo addslashes($str); ?> SEE ALSO
stripcslashes(3), stripslashes(3), addcslashes(3), htmlspecialchars(3), quotemeta(3), get_magic_quotes_gpc(3). PHP Documentation Group ADDSLASHES(3)
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