此示例通过一个包含异常的样例程序说明 dbx 中的异常处理。 在函数 bar 中抛出类型为 int 的异常,并在后面的 catch 块中捕获该异常。
1 #include <stdio.h> 2 3 class c { 4 int x; 5 public: 6 c(int i) { x = i; } 7 ~c() { 8 printf("destructor for c(%d)\n", x); 9 } 10 }; 11 12 void bar() { 13 c c1(3); 14 throw(99); 15 } 16 17 int main() { 18 try { 19 c c2(5); 20 bar(); 21 return 0; 22 } 23 catch (int i) { 24 printf("caught exception %d\n", i); 25 } 26 }
下面摘录的程序示例显示了 dbx 中的异常处理功能。
(dbx) intercept -unhandled -unexpected (dbx) intercept int <dbx> intercept -unhandled -unexpected int (dbx) stop in bar (2) stop in bar() (dbx)run Running: a.out (process id 304) Stopped in bar at line 13 in file “foo.cc” 13 c c1(3); (dbx) whocatches int int is caught at line 24, in function main (frame number 2) (dbx) whocatches c dbx: no runtime type info for class c (never thrown or caught) (dbx) cont Exception of type int is caught at line 24, in function main (frame number 4) stopped in _exdbg_notify_of_throw at 0xef731494 0xef731494: _exdbg_notify_of_throw : jmp %o7 + 0x8 Current function is bar 14 throw(99); (dbx) step stopped in c::~c at line 8 in file "foo.cc" 8 printf("destructor for c(%d)\n", x); (dbx) step destructor for c(3) stopped in c::~c at line 9 in file "foo.cc" 9 } (dbx) step stopped in c::~c at line 8 in file "foo.cc" 8 printf("destructor for c(%d)\n", x); (dbx) step destructor for c(5) stopped in c::~c at line 9 in file "foo.cc" 9 ) (dbx) step stopped in main at line 24 in file "foo.cc" 24 printf("caught exception %d\n", i); (dbx) step caught exception 99 stopped in main at line 26 in file "foo.cc" 26 }