(Thanks for helping with my last question; here's another:)
re_pattern_buffer contains the following three fields:
/* If set, a beginning-of-line anchor doesn't match at the beginning
of the string. */
unsigned __REPB_PREFIX(not_bol) : 1;
/* Similarly for an end-of-line anchor. */
unsigned __REPB_PREFIX(not_eol) : 1;
/* If true, an anchor at a newline matches. */
unsigned __REPB_PREFIX(newline_anchor) : 1;
These look as though it should be possible to set them before calls to
re_search and friends, rather like the POSIX execution flags
REG_NOTBOL &c. However, the only documentation I can find says (of
re_pattern_buffer):
/* This data structure represents a compiled pattern. Before calling
the pattern compiler, the fields `buffer', `allocated', `fastmap',
`translate', and `no_sub' can be set. After the pattern has been
compiled, the `re_nsub' field is available. All other fields are
private to the regex routines. */
Note in particular that last sentence. Is is true? Looking at the code
suggests the opposite: regexec.c contains the following:
eflags |= (bufp->not_bol) ? REG_NOTBOL : 0;
eflags |= (bufp->not_eol) ? REG_NOTEOL : 0;
Unfortunately I can only tell from this that I could use not_bol &
friends as I imagine in practise, not that it's intended behavior on
which I can rely...
--
http://rrt.sc3d.org
