Gdb commands required for iOS development

Updated Description: This article is described comprehensively later.
Http://blog.csdn.net/ch_soft/article/details/6740000

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GDB is not omnipotent, but it is absolutely impossible without GDB. Here is a brief introduction to the most basic gdb commands in iOS development.

Po

Po is short for print-object and can be used to print all nsobject objects. Example:

(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 is short for print and can be used to print all simple types, such as int, float, and struct. Example:

(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 = {

Length = 320,

Height = 411

}

(GDB) print
(Cgsize) [[self view] size]

$2 = {

Length = 320,

Height = 411

}

Call

Call is called. In fact, the above Po and P also have the calling function. Therefore, call is generally used only when no output is displayed or the method does not return a value. Example:

(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]