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The format string syntax and semantics is the same for all of the functions in the printf-like family. Mismatch between the format specifiers and count and type of values can cause a crash or vulnerability. The printf format string is complementary to the scanf format string, which provides formatted input (lexing a.k.a. parsing). Both format ...
^c The ALGOL 68, C and C++ languages do not specify the exact width of the integer types short, int, long, and (C99, C++11) long long, so they are implementation-dependent. In C and C++ short , long , and long long types are required to be at least 16, 32, and 64 bits wide, respectively, but can be more.
printf(string format, items-to-format) It can take one or more arguments, where the first argument is a string to be written. This string can contain special formatting codes which are replaced by items from the remainder of the arguments. For example, an integer can be printed using the "%d" formatting code, e.g.: printf("%d", 42);
Both take one argument that specifies the formatting of the output, and any number of arguments that provide the values to be formatted. Variadic functions can expose type-safety problems in some languages. For instance, C's printf, if used incautiously, can give rise to a class of security holes known as format string attacks.
If the format is used for executables, the design also affects the time programs take to begin running, and thus the responsiveness for users. The GNU Project 's Binary File Descriptor library (BFD library) provides a common API for the manipulation of object files in a variety of formats.
The main difference is that C uses a "format string" that is interpreted to find the arguments to the printf function and convert them, whereas Pascal performs that under the control of the language processor. The Pascal method is arguably faster, because no interpretation takes place, but the C method is highly extensible.
The problem stems from the use of unchecked user input as the format string parameter in certain C functions that perform formatting, such as printf(). A malicious user may use the %s and %x format tokens, among others, to print data from the call stack or possibly other locations in memory.
The command accepts a format string, which specifies how to format values, and a list of values. Characters in the format string are copied to the output verbatim except when a format specifier is found which causes a value to be output. In addition to the standard format specifiers, %b causes the command to expand backslash escape sequences ...