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Write a routine bfree(p,n) that will free an arbitrary block p of n characters into the free list maintained by malloc and free. By using bfree, a user can add a static or external array to the free list at any time. Solution of unknown origin. /* bfree(): Exercise from K&R 8-8; Ads an arbitrary block into the free * ** list maintained by malloc() and free() as written by K&R in chapter 8* ** Me..

/* * Filename: malloc-safer.c * Author: Andrew Suzuki * Date: 06/12/2015 * * Exercise 8-7. malloc accepts a size request without checking its plausibility; * free believes that the block it is asked to free contains a valid size field. * Improve these routines so they take more pains with error checking. */ #include #include #include #include typedef long Align; /* for alignment to long boundary..

The standard library function calloc(n,size) returns a pointer to n objects of size size , with the storage initialized to zero. Write calloc , by calling malloc or by modifying it. Solution by Bryan Williams /* Exercise 8.6. The standard library function calloc(n, size) returns a pointer to n objects of size size, with the storage initialised to zero. Write calloc, by calling malloc or by modif..

Modify the fsize program to print the other information contained in the inode entry. Solution by Akil Adeshwar /* Modify the fsize program to print the other information contained in the inode entry. */ #include #include #include #include #include #include #include #include #define MAX_PATH 1024 #ifndef DIRSIZ #define DIRSIZ 14 #endif void dirwalk( char *dir,void (*fcn)(char *)){ char name[MAX_..

The standard library function int fseek(FILE *fp, long offset, int origin) is identical to lseek except that fp is a file pointer instead of a file descriptor and the return value is an int status, not a position. Write fseek . Make sure that your fseek coordinates properly with the buffering done for the other functions of the library. Solution by Gregory Pietsch Here's Gregory's first solution..

Design and write _flushbuf , fflush , and fclose . Solution by Gregory Pietsch /* Editor's note: Gregory didn't supply a main() for this. Normally, in these situations, * I'd supply one Richard Heathfield, so that you can easily run and test the code. But, in this case, * I wouldn't know where to start! If anyone wants to fill the gap, please let Richard Heathfield know. * Thanks. * RJH, 28 June..

Rewrite fopen and _fillbuf with fields instead of explicit bit operations. Compare code size and execution speed. Solution by Akil Adeshwar /* Rewrite fopen and _fillbuf with fields instead of explicit bit operations. To avoid confusion, my implementation of standard definitions have a suffix "x" Field based approach is time consuming as we would have to check if each field is set or not while f..

Rewrite the program cat from Chapter 7 using read , write , open and close instead of their standard library equivalents. Perform experiments to determine the relative speeds of the two versions. Solution by Andrew Tesker /* Andrew Tesker ucat.c a version of cat using UNIX system access */ #include #include #define BUFSIZE 1024 int main(int argc, char *argv[]) { int fd1; void filecopy(int f, int..

Functions like isupper can be implemented to save space or to save time. Explore both possibilities. Solution by Gregory Pietsch This question is best left to an essay rather than code, so here's my take: The easiest way to implement the eleven is() functions in C90's version of is via a table lookup. If UCHAR_MAX is 255, then a table would take up around 514 8-bit bytes and still have room for ..

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..