view toys/lsb/seq.c @ 845:44ed476d5c87

Fix argument parsing so -- doesn't include itself in output.
author Rob Landley <>
date Sat, 06 Apr 2013 19:57:54 -0500
parents 41b067739bd0
line wrap: on
line source

/* seq.c - Count from first to last, by increment.
 * Copyright 2006 Rob Landley <>


config SEQ
  bool "seq"
  depends on TOYBOX_FLOAT
  default y
    usage: seq [-f fmt_str] [-s sep_str] [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.

    -f	Use fmt_str as a floating point format string
    -s	Use sep_str as separator, default is a newline character

#define FOR_seq
#include "toys.h"

  char *sep;
  char *fmt;

void seq_main(void)
  double first, increment, last, dd;
  char *sep_str = "\n";
  char *fmt_str = "%g";
  int output = 0;

  // 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]);

  if (toys.optflags & FLAG_f) fmt_str = TT.fmt;
  if (toys.optflags & FLAG_s) sep_str = TT.sep;

  // 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);
    if (dd != first) printf("%s", sep_str);
    printf(fmt_str, dd);
    output = 1;

  if (output) printf("\n");