| @node Quoting | |
| @section Quoting | |
| @c Copyright (C) 2005, 2009--2026 Free Software Foundation, Inc. | |
| @c Permission is granted to copy, distribute and/or modify this document | |
| @c under the terms of the GNU Free Documentation License, Version 1.3 or | |
| @c any later version published by the Free Software Foundation; with no | |
| @c Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A | |
| @c copy of the license is at <https://www.gnu.org/licenses/fdl-1.3.en.html>. | |
| @cindex Quoting | |
| @findex quote | |
| @findex quotearg | |
| @mindex quote | |
| @mindex quotearg | |
| Gnulib provides @samp{quote} and @samp{quotearg} modules to help with | |
| quoting text, such as file names, in messages to the user. Here's an | |
| example of using @samp{quote}: | |
| @example | |
| #include <quote.h> | |
| ... | |
| error (0, errno, _("cannot change owner of %s"), quote (fname)); | |
| @end example | |
| This differs from | |
| @example | |
| error (0, errno, _("cannot change owner of '%s'"), fname); | |
| @end example | |
| @noindent in that @code{quote} escapes unusual characters in | |
| @code{fname}, e.g., @samp{'} and control characters like @samp{\n}. | |
| @findex quote_n | |
| However, a caveat: @code{quote} reuses the storage that it returns. | |
| Hence if you need more than one thing quoted at the same time, you | |
| need to use @code{quote_n}. | |
| @findex quotearg_alloc | |
| Also, the @code{quote} module is not suited for multithreaded applications. | |
| In that case, you have to use @code{quotearg_alloc}, defined in the | |
| @samp{quotearg} module, which is decidedly less convenient. |