Yahoo Web Search

Search results

1. Top results related to ansi c print size of variable

   • ANSI C - count the size of the string pointer

     Top Answer

     Answered Jan 15, 2014 · 9 votes

     Remember that strings in C are ended by the null terminator character, written as \0. If you have a well-formed string stored in your pointer variable, you can therefore determine the length by searching for this character:

     char *x = "hello"; // automatically appends a null terminatorint len = 0;while (x[len] != '\0') { len++;}

     If your variables are uninitialized or otherwise not well-formed (e.g., by being NULL) you obviously cannot take this approach; however, most functions are generally written under the assumption that the strings are well-formed, because this leads to faster code.

     If you wish to initialize a pointer, you have three options: NULL, a valid address (e.g., char *x = &someCharVar), or a string constant (e.g., char *x = "hello"). Note that if you use a string constant, it is illegal for you to write into that pointer unless you re-assign to it with the address of a non-constant string.

     // Get enough space for 24 characters plus null terminatorchar *myString = (char*) malloc(25 * sizeof(char));strcpy(myString, "some text"); // fill the new memoryfgets(myString, 25, stdin); // fill with keyboard input

     Note that sizeof(char) is unnecessary here, since a char is always defined to be exactly 1 byte. However, it's a good habit to get into for when you're using other data types, and it helps make your code self-documenting by making your intentions very clear.

     Check all answers on Stack Overflow

     1/5

   • Print size of type :C

     Top Answer

     Answered Nov 15, 2017 · 6 votes

     sizeof

     is an operator computed at compile time. It returns a compile time constant (except for VLAs). In your code, you are always printing sizeof(char*)

     (which happens to be 8 on your and on my computers). Remember that an array is not the same as a pointer, even if arrays decay into pointers.

     You want:

     printf ("sizeof int is %zu\n", sizeof(int));printf ("sizeof long is %zu\n", sizeof(long));

     and you might use preprocessor tricks (stringizing with #

     )

     #define PRINTSIZE(Type) printf("sizeof " #Type " is %zu\n", sizeof(Type))PRINTSIZE(int);PRINTSIZE(long);

     The C language separates translation-time and run-time. Practically speaking, you are using a compiler (and sometimes even a cross-compiler). There is no eval operator in standard C.

     On many operating systems, you can run another compilation process (perhaps using system or popen(3)), but how to run the compiler is system specific (on Linux, you'll often use gcc

     ; on Windows, it probably is something else).

     So in principle you could, on Linux, write a program which generates a temporary C file then uses system(3) on some computed string twice: once to run the compilation, another time to run the produced executable. But that is complex (and not portable), so is not worth your time.

     Notice that, in C (and C++), types, statements, expressions, variables names, etc... are only known to the compiler and don't exist at runtime (when running you only have memory locations). The C11 standard (read n1570) mentions translation units.

     Maybe you dream of some homoiconic programming language. Then don't use C, but languages like Common Lisp. Try SBCL, that Common Lisp implementation is transforming (i.e. compiling) at each REPL interaction your expression into machine code.

     Check all answers on Stack Overflow

     2/5

   • size of reference variable in c++

     Top Answer

     Answered Dec 20, 2012 · 25 votes

     How references are implemented is purely an implementation detail. But Yes, most implementations would implement them using pointers. sizeof operator applied on an reference gives you the size of the element it referes to.

     What is the size of the reference itself?

     C+11 Standard: § 8.3.2.4

     It is unspecified whether or not a reference requires storage (3.7).

     Note that, Unspecified means that an compiler implementation does not need to document how it implements a reference. Neither should you consider the implementation to be anything specific. In short, the language standard treats reference implementation as an detail which user of the language does not need to know and hence it abstracts this detail.

     Check all answers on Stack Overflow

     3/5

   • C - print in Stream array byte with variable size

     Top Answer

     Answered Dec 11, 2014 · 1 votes

     You can use fwrite for writing an arbitrary data with a given length into a file (or device file), not only strings.

     Check all answers on Stack Overflow

     4/5

   • Print part of the int variable in C++

     Top Answer

     Answered Aug 06, 2012 · 4 votes

     You can use math to calculate the area code and the local exchange code for your number:

     • 6152222222 / 10000 drops the last four digits, giving you 615222
     • Further dividing by 1000 gives you 615; taking the remainder of the division by 1000 gives you 222.

     Please note that using an int to represent a telephone number limits your ability to store some more exotic phone numbers, such as 1-800-SOMETHING. Using a class encapsulating a string with additional validations may prove to be a better alternative:

     class phone_number {string phone;public: phone_number(const string& p) { // validate p... if (p.size() != 10) { // Do something violent here... cerr << "The phone number is incorrect." << endl; } // Validate more things about the number before the assignment... phone = p; } friend ostream& operator<<(ostream &os, const phone_number& p);};ostream& operator<<(ostream &os, const phone_number& pn) { const string &p(pn.phone); os << "(" << p.substr(0, 3) << ")" << p.substr(3, 3) << "-" << p.substr(6); return os;}int main() { phone_number p = phone_number("6152784567"); cout << p << endl; return 0;}

     This produces the expected output on ideone.

     Check all answers on Stack Overflow

     5/5

   Show moreShow less

2. People also ask

   How to print a size of a variable in JavaScript?

   • The sizeof(variable) operator computes the size of a variable. And, to print the result returned by sizeof, we use either %lu or %zu format specifier. int intType; float floatType; double doubleType; char charType; // sizeof evaluates the size of a variable printf("Size of int: %zu bytes\ ", sizeof(intType));

   C Program to Find the Size of int, float, double and char

   www.programiz.com/c-programming/examples/sizeof-operator-example

   See all results for this question

   How do I print a value of type size_t in C?

   • In any reasonably modern C implementation, "%zu" is the correct way to print a value of type size_t: The "%zu" format specifier was added in the 1999 ISO C standard (and adopted by the 2011 ISO C++ standard). If you don't need to be concerned about implementations older than that, you can stop reading now.

   c - How can one print a size_t variable portably using the printf

   stackoverflow.com/questions/2524611/how-can-one-print-a-size-t-variable-portably-using-the-printf-family

   See all results for this question

   How do I print a size_t value?

   • The sizeof function returns a size_t type. Try using %zu as the conversion specifier instead of %d. To clarify, use %zu if your compiler supports C99; otherwise, or if you want maximum portability, the best way to print a size_t value is to convert it to unsigned long and use %lu.

   How do I print the size of int in C? - Stack Overflow

   stackoverflow.com/questions/5943840/how-do-i-print-the-size-of-int-in-c

   See all results for this question

   How to control output format in ANSI C?

   • The ostream methods for controlling output format are verbose and clumsy. Some programmers prefer the more compact ANSI C approach. In the previous section we showed how to read a list of and values and create a table in a well-defined format. Here is how to do the same thing with the ANSI C printf function call.

   Formatting with ANSI C printf - University of Utah

   web.physics.utah.edu/~detar/lessons/c /canned_classes/node7.html

   See all results for this question

3. stackoverflow.com › questions › 2524611c - How can one print a size_t variable portably using the ...

   stackoverflow.com › questions › 2524611

   • Cached

   Mar 26, 2010 · In any reasonably modern C implementation, "%zu" is the correct way to print a value of type size_t: printf("sizeof (int) = %zu ", sizeof (int)); The "%zu" format specifier was added in the 1999 ISO C standard (and adopted by the 2011 ISO C++ standard).

   Code sample

   size_t x = ...;

   ssize_t y = ...;

   printf("%zu\n", x); // prints as unsigned decimal

   printf("%zx\n", x); // prints as hex

   printf("%zd\n", y); // prints as signed decimal

   See more on stackoverflow

4. stackoverflow.com › questions › 5943840How do I print the size of int in C? - Stack Overflow

   stackoverflow.com › questions › 5943840

   • Cached

   Mar 9, 2017 · Try using %zu as the conversion specifier instead of %d. printf("The size of integer is %zu ", sizeof(n)); To clarify, use %zu if your compiler supports C99; otherwise, or if you want maximum portability, the best way to print a size_t value is to convert it to unsigned long and use %lu.

   • The sizeof function returns a size_t type. Try using %zu as the conversion specifier instead of %d . printf("The size of integer is %zu\ ", si...
   • Your problem is that size_t is an unsigned type. Try using printf("The size of integer is %u\ ", sizeof(n)); and you should get rid of that warning.
   • I think you should write this instead: printf("The size of integer is %d\ ", sizeof(int));

5. www.programiz.com › c-programming › examplesC Program to Find the Size of int, float, double and char

   www.programiz.com › c-programming › examples

   • Cached

   // sizeof evaluates the size of a variable printf("Size of int: %zu bytes ", sizeof(intType)); printf("Size of float: %zu bytes ", sizeof(floatType)); printf("Size of double: %zu bytes ", sizeof(doubleType)); printf("Size of char: %zu byte ", sizeof(charType)); . return 0; } Run Code. Output. Size of int: 4 bytes. Size of float: 4 bytes

6. www.geeksforgeeks.org › sizeof-operator-csizeof operator in C - GeeksforGeeks

   www.geeksforgeeks.org › sizeof-operator-c

   • Cached

   • Usage of sizeof() Operator
   • Type of Operator
   • Need of sizeof

   sizeof()operator is used in different ways according to the operand type. 1. When the operand is a Data Type: When sizeof()is used with the data types such as int, float, char… etc it simply returns the amount of memory allocated to that data types. Example: 2. When the operand is an expression: When sizeof()is used with the expression, it returns ...

   See full list on geeksforgeeks.org

   sizeof() is a compile-time operator. compile time refers to the time at which the source code is converted to a binary code. It doesn’t execute (run) the code inside (). Example: If we try to increment the value of x, it remains the same. This is because x is incremented inside the parentheses and sizeof() is a compile-time operator.

   See full list on geeksforgeeks.org

   1. To find out the number of elements in an array: Sizeof can be used to calculate the number of elements of the array automatically. Example: 2. To allocate a block of memory dynamically: sizeof is greatly used in dynamic memory allocation. For example, if we want to allocate memory that is sufficient to hold 10 integers and we don’t know the size...

   See full list on geeksforgeeks.org

7. web.physics.utah.edu › ~detar › lessonsFormatting with ANSI C printf - University of Utah

   web.physics.utah.edu › ~detar › lessons

   • Cached

   Here is how to do the same thing with the ANSI C printf function call. Output from printf goes to stdout and may be mixed with cout . #include <stdio.h>. // Write a column header. printf(" x y "); printf("-------------- "); for( i = 0; i < 10; i++) printf("%7.4f%7.4f ",x[i],y[i]);

8. www.includehelp.com › c-programs › c-program-toC program to print size of variables using sizeof() operator

   www.includehelp.com › c-programs › c-program-to

   • Cached

   C program to print size of variables using sizeof () operator. sizeof () is an operator in c programming language, which is used to get the occupied size by the variable or value. This program demonstrate the example of sizeof () operator by printing size of different type of variables.

9. en.wikipedia.org › wiki › C_data_typesC data types - Wikipedia

   en.wikipedia.org › wiki › C_data_types

   • Cached

   size_t is an unsigned integer type used to represent the size of any object (including arrays) in the particular implementation. The operator sizeof yields a value of the type size_t . The maximum size of size_t is provided via SIZE_MAX , a macro constant which is defined in the < stdint.h > header ( cstdint header in C++).