Vcs26

Vcs26

• 1.
  Unformatted Console I/OFunctions main( ) { printf ( ”Delete all files Y/N” ) ; ch = getchar( ) ; /* or ch = fgetchar( ) ; */ putch ( ch ) ; putchar ( ch ) ; fputchar ( ch ) ; } printf ( ”Press any key” ) ; getch( ) ; printf ( ”Another disk Y/N” ) ; ch = getche( ) ; same char ch ;
• 2.
  Peculiarities getch( )- Doesn’t wait for enter. getche( ) - Echoes character. getchar( ) - Waits for enter. Macro. fgetchar( ) - Waits for enter. Function.
• 3.
  Disk I/O HighLevel / Std Disk I/O Low Level Text Binary Formatted Unformatted char int fprintf( ) float fscanf( ) string char - getc ( ), fgetc( ) putc ( ), fputc( ) Reads / Writes char by char int - float - No Std. Library Function string - fgets( ), fputs( ) Reads / Writes line by line file
• 4.
  Bufferred I/O Memory )) Buffer CCHH11PPRR11..CC Disk
• 5.
  Displaying File Contents # include ”stdio.h” char fname[13] ; printf ( ”Enter file name” ) ; gets ( fname ) ; fopen ( ) ; main( ) { char ch ; FILE *fp ; fp = fname, ”r” while ( 1 ) { ch = getc ( ) ; if ( ch == EOF ) break ; printf ( ”%c”, ch ) ; } fclose ( ) ; } fp fp
• 6.
  typedef unsigned longint i, j ; typedef unsigned long int uli ; struct employee { ___ } ; struct employee e1, e2 ; struct a { __ char *p ; } ; typedef struct a FILE ; uli i, j ; struct employee { ___ } ; typedef struct employee emp ; emp e1, e2 ; FILE *fp ;
• 7.
  # include ”stdio.h” char fname[13] ; printf ( ”Enter file name” ) ; gets ( fname ) ; fopen ( ) ; main( ) { char ch ; FILE *fp ; fp = fname, ”r” while ( 1 ) { ch = getc ( ) ; if ( ch == EOF ) break ; printf ( ”%c”, ch ) ; } fclose ( ) ; } fp fp A Fresh Look Buffer 40 fp p 40 ffpp -->> pp == ffpp -->> pp ++ 11 ;;
• 8.
  Tips fopen() - Standard Library Function to open the file. fopen ( fname, ”r” ) ; - Returns NULL if file not found. Every file ends with a char with ascii value 26. EOF is a macro. # define EOF -1 FILE is a structure defined in stdio.h getc( ) reads char also shifts pointer to next char.
• 9.
  Copying Files charfname[13] , target[13] ; printf ( ”Enter source target file names” ) ; gets ( fname ) ; gets ( target ) ; ft = fopen ( target, ”w” ) ; # include ”stdio.h” fopen ( ) ; main( ) { char ch ; FILE *fs, *ft ; fs = fname, ”r” while ( 1 ) { ch = getc ( ) ; if ( ch == EOF ) break ; putc ( ) ; ch, ft } fclose ( ) ; fs fs fclose ( ft ) ; }
• 10.
  Copying Files charfname[13] , target[13] ; printf ( ”Enter source target file names” ) ; gets ( fname ) ; gets ( target ) ; ft = fopen ( target, ”w” ) ; # include ”stdio.h” fopen ( ) ; main( ) { char ch ; FILE *fs, *ft ; fs = fname, ”r” while ( 1 ) { ch = getc ( ) ; if ( ch == EOF ) break ; putc ( ) ; ch, ft } fclose ( ) ; fs fs fclose ( ft ) ; }