<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"> <html lang="en"> <head> <meta http-equiv="Content-Language" content="en-us"> <meta name="GENERATOR" content="Microsoft FrontPage 5.0"> <meta name="ProgId" content="FrontPage.Editor.Document"> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <title>Adding watchpoints</title> <link rel="stylesheet" type="text/css" href="../help.css"> </head> <body> <div role="main"><h1>Adding watchpoints</h1> <p>A watchpoint is a special breakpoint that stops the execution of an application whenever the value of a given expression changes, without specifying where it might occur. Unlike breakpoints (which are line-specific), watchpoints are associated with files. They take effect whenever a specified condition is true, regardless of when or where it occurred. You can set a watchpoint on a global variable by highlighting the variable in the editor, or by selecting it in the Outline view. </p> <p>To set a watchpoint on a global variable:</p> <ol> <li>Highlight the variable in the editor, or select it in the Outline view.</li> <li>Click <strong>Run > Toggle Watchpoint</strong>.</li> <li>Do any of the following: <ul><li>To stop execution when the watch expression is read, select the <strong>Read</strong> check box.</li> <li>To stop execution when the watch expression is written to, select the <strong>Write</strong> check box.</li></ul> </li> <li>The watchpoint appears in the <strong>Breakpoints</strong> view list.</li> </ol> <p><img src="../images/ngconcepts.gif" ALT="Related concepts" width="143" height="21"> <br> <a href="../concepts/cdt_c_over_cdt.htm">C/C++ Development perspective</a></p> <p><img src="../images/ngtasks.gif" ALT="Related tasks" width="143" height="21"> <br> <a href="cdt_o_brkpnts_watch.htm">Using breakpoints and watchpoints</a></p> <p><img src="../images/ngref.gif" ALT="Related reference" width="143" height="21"> <br> <a href="../reference/cdt_o_run_dbg_pages.htm">Run and Debug dialog box</a></p> <img src="../images/ng00_04a.gif" ALT="QNX Copyright Statement" > </div></body> </html>