diff options
Diffstat (limited to 'toys/seq.c')
-rw-r--r-- | toys/seq.c | 47 |
1 files changed, 47 insertions, 0 deletions
diff --git a/toys/seq.c b/toys/seq.c new file mode 100644 index 00000000..8eb8fb8e --- /dev/null +++ b/toys/seq.c @@ -0,0 +1,47 @@ +/* vi: set sw=4 ts=4: + * + * seq.c - Count from first to last, by increment. + * + * Copyright 2006 Rob Landley <rob@landley.net> + * + * Not in SUSv3. (Don't ask me why not.) + +USE_SEQ(NEWTOY(seq, "<1>3?+", TOYFLAG_USR|TOYFLAG_BIN)) + +config SEQ + bool "seq" + default y + help + usage: seq [first] [increment] last + + Count from first to last, by increment. Omitted arguments default + to 1. Two arguments are used as first and last. Arguments can be + negative or floating point. +*/ + +#include "toys.h" + +void seq_main(void) +{ + double first, increment, last, dd; + + // Parse command line arguments, with appropriate defaults. + // Note that any non-numeric arguments are treated as zero. + first = increment = 1; + switch (toys.optc) { + case 3: + increment = atof(toys.optargs[1]); + case 2: + first = atof(*toys.optargs); + default: + last = atof(toys.optargs[toys.optc-1]); + } + + // Yes, we're looping on a double. Yes rounding errors can accumulate if + // you use a non-integer increment. Deal with it. + for (dd=first; (increment>0 && dd<=last) || (increment <0 && dd>=last); + dd+=increment) + { + printf("%g\n", dd); + } +} |