escaping

I am trying to define a pattern to match text with a question mark (?) inside it. In the regex the question mark is considered a 'once or not at all'. So can i replace the (?) sign in my text with (\\?) to fix the pattern problem ? String text = "aaa aspx?pubid=222 zzz"; Pattern p = Pattern.compile( "aspx?pubid=222" ); Matcher m = p.matcher( text ); if ( m.find() ) System.out.print( "Found it." ); else System.out.print( "Didn't find it." ); // Always prints. You need to escape ? as \\? in the regular expression and not in the text . Pattern p = Pattern.compile( "aspx\\?pubid=222" ); See it You

I would still like to know how to pass in a null character as a command line argument, maybe so that a single string can be passed in as an argument in the form: "to\0be\0or\0not\0to\0be\0" And then parse it. However the program would treat this string as: "to\\0be\\0or\\0not\\0to\\0be\\0" How can I work around this? Is there any way? You cannot. The C program receives arguments as zero-terminated strings. Such a string cannot contain a null character, by definition. If you want to pass a null character, then you must somewhat encode it with some syntax, and your C program must then decode it

When searching for underscores in Postgresql, literal use of the character _ doesn't work. For example, if you wanted to search all your tables for any columns that ended in _by , for something like change log or activity information, e.g. updated_by , reviewed_by , etc., the following query almost works: SELECT table_name, column_name FROM information_schema.columns WHERE column_name LIKE '%_by' It basically ignores the underscore completely and returns as if you'd searched for LIKE '%by' . This may not be a problem in all cases, but it has the potential to be one. How to search for

How can you escape _ without the use of \_ ? This is the example of the question word_a_a_a_a_a_b_c_dd There is one function which you can use for this. However, I cannot remember its name. Are you thinking of the underscore package, which redefines the underscore symbol so that you don't have to escape it in text mode? See here . Other than verbatim I wouldn't know. Verbatim environment: \begin{verbatim} word_a_a_a_a_a_b_c_dd \end{verbatim} Inline: \verb|word_a_a_a_a_a_b_c_dd| I couldn't get the underscore package to work, so I used the url package: \usepackage{url} \urlstyle{sf} % or rm,

I have a python dictionary e.g.: [{"pk":"1","name":"John","size":"1/4" "},{},{},etc] That size is 1/4 inch,how would I "escape" that quote? So it still would display it as 1/4", Its a list of things, so I cant just manually code it like 1/4\" , I tried replace('"','\"') EDIT: The orginal list is a textfield in my Django models: [{'pk': '91', 'size': '', 'name': 'Thread Flat For BF', 'quantity': '2'}, {'pk': '90', 'size': '', 'name': 'Blade Holders Straight ', 'quantity': '26'},{'size':'3"','name':'2m 1/4" Round bar', 'quantity':'43'},{'size':'5','name':'2m 1/8" Round bar', 'quantity':'4'}]

I.e.: How to suppress substitution/replacement of characters with its html entities in a MediaWiki link? I need to insert a link looking like this, pipes ( | ) included, into a MediaWiki article: http://www.somesite.asdf/#|param1|param2|param3 The target site does not accept %7C or | as pipe-substitutes in its URL. Ergo, the following URLs are invalid: http://www.somesite.asdf/#%7Cparam1%7Cparam2%7Cparam3 http://www.somesite.asdf/#|param1|param2|param3 When I type the link into the MediaWiki-article like: http://www.somesite.asdf/#|param1|param2|param3 ... it results in a link pointing to:

My knowledge of commandline bash is missing on a particular area: I constantly forget how to properly escape characters. Today I wanted to echo this string into a file: #!/bin/env bash python -m SimpleHTTPServer However, this fails: echo "#!/bin/env bash\npython -m SimpleHTTPServer" > server.sh && chmod +x server.sh -bash: !/bin/env: event not found That's right: Remember to escape ! or bash will think it's a special bash event command. But I can't get the escaping right! \! yields \! in the echoed string, and so does \\! . Furthermore, \n will not translate to a line break. Do you have some