01-12-2010
Quote:
Originally Posted by
tlarkin
Thanks for your reply, but still got a few questions...
According to this document, which I have used to teach myself shell programming, [[ and [ have different abilities in bash.
Yes, BASH has many extensions on the standard shell. But you can't depend on those extensions anywhere else.
As for numerical and string equality being identical, well -- given the same number base and no leading zeroes or extraneous sign symbols, a string comparison is no different than a numerical comparison. I've tried various things to trip them up, things like comparing positive and negative zero... it always acts just like a string comparison whether its one or two equals.
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LEARN ABOUT DEBIAN
fstrcmp
fstrcmp(3) Library Functions Manual fstrcmp(3)
NAME
fstrcmp - fuzzy comparison of two strings
SYNOPSIS
#include <fstrcmp.h>
#define FSTRCMP_IDENTICAL
#define FSTRCMP_THRESHOLD
#define FSTRCMP_ERROR
double fstrcmp(const char *string1, const char *string2);
DESCRIPTION
The fstrcmp() function compares the two strings, string1 and string2.
RETURN VALUE
The fstrcmp function returns a floating point value between 0.0 and FSTRCMP_IDENTICAL. A value of 0.0 means the strings are utterly un-
alike. A value of FSTRCMP_IDENTICAL means the strings are identical. A value of more than FSTRCMP_THRESHOLD (it lies between 0.0 and
FSTRCMP_IDENTICAL) would be considered "similar" by most people.
A value of FSTRCMP_ERROR (always negative) indicates a malloc(3) failure.
SEE ALSO
fmemcmp(3)
fuzzy comparison of two memory areas
fstrcasecmp(3)
fuzzy comparison of two strings ignoring case
fstrcmpi(3)
fuzzy comparison of two strings
strcmp(3)
compare two strings
COPYRIGHT
fstrcmp version 0.4
Copyright (C) 2009 Peter Miller
Peter Miller <pmiller@opensource.org.au>
The comparison code is derived from the fuzzy comparison functions in GNU Gettext 0.17. The GNU Gettext comparison functions were, in
turn, derived from GNU Diff 2.7.
Copyright (C) 1988-2009 Free Software Foundation
fstrcmp(3)