What is the role and purpose of the second-level pointer ?. XML

Pre {Line-Height: 1; color: #9f1d66; Background-color: # e1e1e1; font-size: 16px ;}. sysfunc {color: # 5d57ff; font-style: italic; font-weight: bold ;}. selffuc {color: #8e0ed3 ;}. bool {color: #008000 ;}. condition {color: #008000; font-weight: bold ;}. key {color: #440080 ;}. vaR {color: #008000; font-style: italic ;}. digit {color: #000080; font-weight: bold ;}. includepre {color: # 661d9f ;}. operator? {Color: # fd1a53; font-weight: bold ;}

???? The second-level pointer ** P is defined not to use ** P to represent the point value, but to use * P to store the address of the unit storing the value .?????

　

???? Void? Getmemory2 (Char? ** P ,? Int? Num )?????? {?????????? * P? =? (Char? *) Malloc (Num );??????}?????? Void? Test (void )?????? {??????????? Char? * Str? =? NULL ;??????????? Getmemory (& STR ,? 100 );??????????? Strcpy (STR ,? "Hello ");?????????????? Printf (STR );??????????????? Free? STR ;??????}???????? When parameters are passed at the beginning, the Unit Address of STR is assigned to P ,?? In this way, the Unit Storage in P is the STR address ,?? Thus, * P? Represents the STR value.

Used in this article? Calligraphy and painting novel software? Released, the content has nothing to do with the software, and the painting and calligraphy novel software? More comfortable reading, more comfortable writing, and easier Publishing.

What is the role and purpose of the second-level pointer ?. XML