Difference between fprintf printf and sprintf

Question

Can anyone explain in simple English about the differences between printf   fprintf  and sprintf with examples   What stream is it in   I m really confused between the three of these while reading about  File Handling in C

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In C  a  stream  is an abstraction  from the program s perspective it is simply a producer  input stream  or consumer  output stream  of bytes   It can correspond to a file on disk  to a pipe  to your terminal  or to some other device such as a printer or tty   The FILE type contains information about the stream   Normally  you don t mess with a FILE object s contents directly  you just pass a pointer to it to the various I O routines     There are three standard streams  stdin is a pointer to the standard input stream  stdout is a pointer to the standard output stream  and stderr is a pointer to the standard error output stream   In an interactive session  the three usually refer to your console  although you can redirect them to point to other files or devices     myprog  lt  inputfile dat  gt  output txt 2 gt  errors txt   In this example  stdin now points to inputfile dat  stdout points to output txt  and stderr points to errors txt     fprintf writes formatted text to the output stream you specify      printf is equivalent to writing fprintf stdout       and writes formatted text to wherever the standard output stream is currently pointing   sprintf writes formatted text to an array of char  as opposed to a stream

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printf      is equivalent to fprintf stdout        fprintf is used to output to stream   sprintf buffer       is used to format a string to a buffer   Note there is also vsprintf  vfprintf and vprintf

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fprintf This is related with streams where as printf is a statement similar to fprintf but not related to streams  that is fprintf is file related

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sprintf  Writes formatted data to a character string in memory instead of stdout  Syntax of sprintf is    include  lt stdio h gt  int sprintf  char  string  const char  format   item   item          Here   String refers to the pointer to a buffer in memory where the data is to be written   Format refers to pointer to a character string defining the format   Each item is a variable or expression specifying the data to write   The value returned by sprintf is greater than or equal to zero if the operation is successful or in other words the number of characters written  not counting the terminating null character is returned and returns a value less than zero if an error occurred   printf  Prints to stdout  Syntax for printf is   printf format  argument       The only difference between sprintf   and printf   is that sprintf   writes data into a character array  while printf   writes data to stdout  the standard output device

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printf outputs to the standard output stream  stdout   fprintf goes to a file handle  FILE    sprintf goes to a buffer you allocated   char

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printf   printf is used to perform output on the screen  syntax   printf  control string    argument    It is not associated with File input output   fprintf   The fprintf it used to perform write operation in the file pointed to by FILE handle  The syntax is fprintf  filename   control string    argument    It is associated with file input output

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You can also do very useful things with vsnprintf   function     cat test cc  include  lt exception gt   include  lt stdarg h gt   include  lt stdio h gt   struct exception fmt   std  exception       exception fmt char const  fmt         attribute     format printf 2 3         char const  what   const throw     return msg         char msg  0x800       exception fmt  exception fmt char const  fmt             va list ap      va start ap  fmt       vsnprintf msg   sizeof msg   fmt  ap       va end ap      int main int ac  char   av        throw exception fmt   s  bad number of arguments  d    av  ac        g   -Wall -o test test cc      test terminate called after throwing an instance of  exception fmt    what       test  bad number of arguments 1 Aborted  core dumped

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printf  quot format quot   args  is used to print the data onto the standard output which is often a computer monitor  sprintf char     quot format quot   args  is like printf  Instead of displaying the formated string on the standard output i e  a monitor  it stores the formated data in a string pointed to by the char pointer  the very first parameter   The string location is the only difference between printf and sprint syntax  fprintf FILE  fp   quot format quot   args  is like printf again  Here  instead of displaying the data on the monitor  or saving it in some string  the formatted data is saved on a file which is pointed to by the file pointer which is used as the first parameter to fprintf  The file pointer is the only addition to the syntax of printf  If stdout file is used as the first parameter in fprintf  its working is then considered equivalent to that of printf

[c] Difference between fprintf, printf and sprintf?

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