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Write a program to print a set of files, starting each new one on a new page, with a title and a running page count for each file. Solution by Steven Huang . /* K&R Exercise 7-8 */ /* Steven Huang */ /* Limitation: This program doesn't wrap long lines. */ #include #include #include #define LINES_PER_PAGE 10 #define TRUE 1 #define FALSE 0 void print_file(char *file_name) { FILE *f; int page_numbe..

Modify the pattern finding program of Chapter 5 to take its input from a set of named files or, if no files are named as arguments, from the standard input. Should the file name be printed when a matching line is found? Solution by Barrett Drawdy /* * K&R2 exercise 7-7 By: Barrett Drawdy * * Modify the pattern finding program of Chapter 5 (on page 117) to take its * input from a set of named fil..

Write a program to compare two files, printing the first line where they differ. Solutions by Rick Dearman and Flippant Squirrel . Here's Rick's solution: /****************************************************** KnR 7-6 -------- Write a program to compare two files and print the first line where they differ. Author: Rick Dearman email: rick@ricken.demon.co.uk Note: This program prints ALL the lin..

Rewrite the postfix calculator of Chapter 4 to use scanf and/or sscanf to do the input and number conversion. Solution by Toni Romic /* K&R Exercise 7-5 */ /* Toni Romic */ #include #include #define MAXOP 100 /* max size of operand or operator */ void push(double); double pop(void); int main() { char *c; char s[MAXOP], buf[MAXOP]; double a = 0, op2; char e = '\0'; while (scanf("%s%c", s, &e) == ..

It seems that the real scanf doesn't handle floats and strings the way I expect it to. Having said that, the book's example of a rudimentary calculator on page 141 does not work on my machine. Here is a solution that only handles integers. /* Thomas Amundsen - K&R2 Exercise 7-4 - 2009-06-19 */ #include #include void minscanf(char *fmt, ...); int main() { int i; minscanf("%d", &i); /* scan intege..

Revise minprintf to handle more of the other facilities of printf . Solution by Gregory Pietsch /* Gregory Pietsch - K&R2 Exercise 7-3 - 2001-01-28 gkp@flash.net */ #include #include /* minprintf: minimal printf with variable argument list */ void minprintf(char *fmt, ...) { va_list ap; char *p, *sval; int ival; double dval; unsigned uval; va_start(ap, fmt); /* make ap point to the first unnamed..

Write a program that will print arbitrary input in a sensible way. As a minimum, it should print non-graphic characters in octal or hexadecimal according to local custom, and break long text lines. Solution by Richard Heathfield /* Use -o for octal output, -x for hexadecimal */ #include #define OCTAL 8 #define HEXADECIMAL 16 void ProcessArgs(int argc, char *argv[], int *output) { int i = 0; whil..

Write a program that converts upper case to lower or lower case to upper, depending on the name it is invoked with, as found in argv[0]. Solution by Richard Heathfield /* This program converts its input to upper case * (if argv[0] begins with U or u) or lower case. * If argc is 0, it prints an error and quits. */ #include #include #include int main(int argc, char **argv) { int (*convcase[2])(int..

Implement a simple version of the #define processor (i.e., no arguments) suitable for use with C programs, based on the routines of this section. You may also find getch and ungetch helpful. Solution by Akil Adeshwar /* Implement a simple version of the #define processor (i.e., no arguments) suitable for use with C programs, based on the routines of this section. You may also find getch and unge..

Write a function undef that will remove a name and definition from the table maintained by lookup and install . Solutions by Paul Griffiths and Gregory Pietsch int undef(char * name) { struct nlist * np1, * np2; if ((np1 = lookup(name)) == NULL) /* name not found */ return 1; for ( np1 = np2 = hashtab[hash(name)]; np1 != NULL; np2 = np1, np1 = np1->next ) { if ( strcmp(name, np1->name) == 0 ) { ..