56 Chapter 8. Examining the StackFor example:(gdb) up#1 0x22f0 in main (argc=1, argv=0xf7fffbf4, env=0xf7fffbfc)at env.c:1010 read_input_file (argv[i]);After such a printout, the list command with no arguments prints ten lines centered on the pointof execution in the frame. You can also edit the program at the point of execution with your favoriteediting program by typing edit. Refer to Section 9.1 Printing source lines for details.up-silently ndown-silently nThese two commands are variants of up and down, respectively; they differ in that they do theirwork silently, without causing display of the new frame. They are intended primarily for use ingdb command scripts, where the output might be unnecessary and distracting.8.4. Information about a frameThere are several other commands to print information about the selected stack frame.framefWhen used without any argument, this command does not change which frame is selected, butprints a brief description of the currently selected stack frame. It can be abbreviated f. With anargument, this command is used to select a stack frame. Refer to Section 8.3 Selecting a frame.info frameinfo fThis command prints a verbose description of the selected stack frame, including:• the address of the frame• the address of the next frame down (called by this frame)• the address of the next frame up (caller of this frame)• the language in which the source code corresponding to this frame is written• the address of the frame’s arguments• the address of the frame’s local variables• the program counter saved in it (the address of execution in the caller frame)• which registers were saved in the frameThe verbose description is useful when something has gone wrong that has made the stack formatfail to fit the usual conventions.
