<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN"> <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> <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 this may happen. 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. To set a watchpoint on a global variable highlight the variable in the editor or select 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 <b>Run > Toggle Watchpoint</b>.</li> <li>Do any of the following:</li> <ul><li>To stop execution when the watch expression is read, select the <b>Read</b> check box.</li> <li>To stop execution when the watch expression is written to, select the <b>Write</b> check box.</li></ul> <li>The watchpoint appears in the <b>Breakpoints</b> view list.</li> </ol> <p><img border="0" 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 border="0" src="../images/ngtasks.gif" ALT="Related tasks" width="143" height="21"> <br> <a href="cdt_o_brkpnts_watch.htm">Working with breakpoints and watchpoints</a></p> <p><img border="0" 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="IBM Copyright Statement" > </body> </html>