iOS開發之不得不會的gdb命令

更新說明：後面發現這篇文章介紹的比較全面
http://blog.csdn.net/ch_soft/article/details/6740000

文章轉載於：http://www.ethangao.com/?p=273，謝謝作者分享。

gdb不是萬能的，可是沒有gdb卻是萬萬不能的。這裡給大家簡單介紹下iOS開發中最基本的gdb命令。

po

po是print-object的簡寫，可用來列印所有NSObject對象。使用舉例如下：

(gdb) po
self

<LauncherViewController: 0x552c570>

(gdb) po
[self view]

<UIView: 0x544eb80; frame = (0 0; 320 411); autoresize = W+H; layer = <CALayer: 0x544ebb0>>

(gdb) print-object
[self view]

<UIView: 0x544eb80; frame = (0 0; 320 411); autoresize = W+H; layer = <CALayer: 0x544ebb0>>

p

p是print的簡寫，可以用來列印所有的簡單類型，如int, float，結構體等。使用舉例如下：

(gdb) p
self

$1 = (LauncherViewController *) 0x552c570

(gdb) p
[[self view] size]

Unable to call function “objc_msgSend” at 0x1e7e08c: no return type information available.

To call this function anyway, you can cast the return type explicitly (e.g. ‘print (float) fabs (3.0)’)

(gdb) p
(CGSize)[[self view] size]

$1 = {

width = 320,

height = 411

}

(gdb) print
(CGSize)[[self view] size]

$2 = {

width = 320,

height = 411

}

call

call即是調用的意思。其實上述的po和p也有調用的功能。因此一般只在不需要顯示輸出，或是方法無傳回值時使用call。使用舉例如下：

(gdb) call
[[self view]sizeToFit]

Unable to call function “objc_msgSend” at 0x1e7e08c: no return type information available.

To call this function anyway, you can cast the return type explicitly (e.g. ‘print (float) fabs (3.0)’)

(gdb) call
(void)[[self view]sizeToFit]

(gdb) call
[[self view] size]

Unable to call function “objc_msgSend” at 0x1e7e08c: no return type information available.

To call this function anyway, you can cast the return type explicitly (e.g. ‘print (float) fabs (3.0)’)

(gdb) call
(void)[[self view] size]