How to mask %....% in string "....."?

[pstein]

From a DOS batch script I want to pass a command/string to a program (here:mysql.exe)
This string parameter contains a %....% token which should NOT be replaced by a DOS batch variable but passed exactly as written to mysql.exe
From cmdline it works fine.

How can I prevent replacement? The percentage sign MUST be passed to mysql.

The following does NOT work:

mysql.exe -u myuser -pmypasswd -e "show variables like '%version%';"

mysql.exe -u myuser -pmypasswd -e "show variables like '\%version\%';"

So how could that work?

Thank you
Peter

[Ed Dyreen]

'
Hi pstein,

unfortunately CMD does not support regular expressions, try:

Code: Select all

mysql.exe -u myuser -pmypasswd -e "show variables like '%%version%%';"

[orange_batch]

There are a few characters that need special handling in batch.

The caret character ^ is batch's escape character, so you would write & like ^&.

It's preferable to write characters within quotation marks (special character processing is disabled within quotation marks, so no problematic carets are needed).

The only two exceptions to that are ! (when delayedexpansion is enabled, needs any number of preceding carets) and %, like your case.

% is easy though. Simply double the character up. %% = %. This is why for loops require %% for its tokens within batch scripts, and not when directly on the command line.