Software 1 - Files and I/O(10)

administrivia

Web Page - http://www.cs.tau.ac.il/~efif/courses/Software1_Spring_04

Initializing a complex struct

• A struct that contains an array

  typedef struct soldier { int id; char name[64]; char *rank; } Soldier; int main() { Soldier s0, s1, s2 = {5705706, "Enzo Agada", "General"}; s0.id = 5705705; strcpy(s0.name, "John Dow"); /* incorrect: s0.name = "John Dow"; */ s0.rank = "Captain"; /* uncorrect: strcpy(s0.rank, "Capitan"); */ s1 = s0; printf("%d %s %s\n", s0.id, s0.name, s0.rank); printf("%d %s %s\n", s1.id, s1.name, s1.rank); printf("%d %s %s\n", s2.id, s2.name, s2.rank); }

• Prints:

  5705705 John Dow Captain 5705705 John Dow Captain 5705706 Enzo Agada General

Opening and closing a file

• fopen - opens a file

  FILE * fopen (const char * filename, const char * mode);

• fclose - closes a file

  int fclose (FILE * stream);

• cat - concatenate files and print on the standard output.
  • Demostrate fopen, fclose, getc, putc, stdin, and stdout
  my_cat.c

Reposition stream's position indicator

• fseek

  int fseek ( FILE * stream , long offset , int origin );

• ftell

  long ftell ( FILE * stream );

• search and replace
  • demostrate fopen, fclose, fseek, ftell, fgets, fprintf, and fflush.
  files.c