1 /* rev.c - reverse lines of a set of given input files 2 * 3 * Copyright 2012 Elie De Brauwer <eliedebrauwer (at) gmail.com> 4 5 USE_REV(NEWTOY(rev, NULL, TOYFLAG_USR|TOYFLAG_BIN)) 6 7 config REV 8 bool "rev" 9 default y 10 help 11 usage: rev [FILE...] 12 13 Output each line reversed, when no files are given stdin is used. 14 */ 15 16 #include "toys.h" 17 18 static void do_rev(int fd, char *name) 19 { 20 char *c; 21 22 for (;;) { 23 int len, i; 24 25 if (!(c = get_line(fd))) break; 26 len = strlen(c) - 1; 27 for (i = 0; i <= len/2; i++) { 28 char tmp = c[i]; 29 30 c[i] = c[len-i]; 31 c[len-i] = tmp; 32 } 33 xputs(c); 34 free(c); 35 } 36 } 37 38 void rev_main(void) 39 { 40 loopfiles(toys.optargs, do_rev); 41 } 42
