C does not, at bottom, have strings. It views them as arrays of
single characters.
When it was realized that this is at best a dubious notion,
nul-delimited strings were grafted on to the structure of C, and the
scar tissue shows.
It is, however, possible to declare a string without specifying its
length, using its initializing value to specify its length implicitly.
Thus
char animal_name[] = 'wombat' ;
yields a six-character string that occupies seven characters of
storage inclusive of its EOS delimiter, x'00' or nul.
The constructions
char animal_name[5] = {'w','o','m','b','a','t'}
char animal_name[5] = 'wombat' ;
are rejected because their initializing values are incompatible with
their length specifications.
Elsewhere--in PL/I and its dialects, DB2, etc--strings are of two
different sorts, non-varying and varying, are also supported.
Varying strings are prefixed by, usually, a halfword current-length indicator.
Thus in PL/I
declare example character(254) varying ;
yields a string occupying 256 bytes, a halfword prefix followed by at
most 254 value bytes, with
0 <= currentlength(example) <= 254.
John Gilmore, Ashland, MA 01721 - USA
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