Possible Duplicate:
How to get rid ofdeprecated conversion from string constant to ‘char*’warnings in GCC?
This assignment:
char *pc1 = "test string";
gives me this warning:
warning: deprecated conversion from string constant to 'char*'
while this one seems to be fine:
char *pc2 = (char*)("test string");
Is this one a really better way to proceed?
Notes: for other reasons I cannot use a const char*.
By string literal : Java String literal is created by using double quotes. For Example: String s=“Welcome”; By new keyword : Java String is created by using a keyword “new”. For example: String s=new String(“Welcome”);
The only difference is that you cannot modify string literals, whereas you can modify arrays. Functions that take a C-style string will be just as happy to accept string literals unless they modify the string (in which case your program will crash).
A string literal is a sequence of zero or more characters enclosed within single quotation marks. The following are examples of string literals: 'Hello, world!' 'He said, "Take it or leave it."'
C Language Undefined behavior Modify string literalAttempting to modify the string literal has undefined behavior. However, modifying a mutable array of char directly, or through a pointer is naturally not undefined behavior, even if its initializer is a literal string.
A string literal is a const char[] in C++, and may be stored in read-only memory so your program will crash if you try to modify it. Pointing a non-const pointer at it is a bad idea.
In your second example, you must make sure that you don't attempt to modify the the string pointed to by pc2.
If you do need to modify the string, there are several alternatives:
Make a dynamically-allocated copy of the literal (don't forget to free() it when done):
char *pc3 = strdup("test string"); /* or malloc() + strcpy() */
Use an array instead of a pointer:
char pc4[] = "test string";
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