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Re: usr.bin/mail: cmd3.c:bangexp(): "borked"?, and BSD fails POSIX compat
Steffen Nurpmeso wrote in
<20230502214014._zIz6%steffen%sdaoden.eu@localhost>:
|Hallo, and sorry for the cross-post, but so all in one (maybe) go.
|
|This is about a niche "feature" of mail, the shell command "bang"
|(! / ~! in compose mode):
...
|POSIX now says / will say
|
| If the bang variable is set, each unescaped occurrence of '!' in
| command shall be replaced with the command executed by the
| previous ! command or ˜! command escape.
|
|thus
|
| - All commands entered for ! and ~! shall be stored.
|
| - If "bang" is set, an unquoted ! shall be replaced by that
| storage.
...
|It will fail to properly "bang" a second time[.]
Eh, forget this please. Of course not, one simply inserts the old
string without expansion.
Since vim(1) offers the same "bang"ing, and merges \! to ! (source
comment speaks of vi-compat) i keep it. (It actually requires
'\!' or \\! ro avoid its expansion in ":echo BLA".)
Ciao.
static struct str last_bang;
struct n_string xbang, *bang;
char c;
char const *cp_orig;
boole bangit, changed;
NYD_IN;
bangit = ok_blook(bang);
changed = FAL0;
cp_orig = cp;
for(bang = n_string_creat(&xbang); (c = *cp++) != '0円';){
if(bangit && c == '!'){
changed = TRU1;
if(last_bang.l > 0)
bang = n_string_push_buf(bang, last_bang.s, last_bang.l);
}else{
if(c == '\\' && *cp == '!'){
changed = TRU1;
++cp;
c = '!';
}
bang = n_string_push_c(bang, c);
}
}
if(last_bang.s != NIL)
su_FREE(last_bang.s);
last_bang.s = n_string_cp(bang);
last_bang.l = bang->s_len;
bang = n_string_drop_ownership(bang);
n_string_gut(bang);
if(bangit){
cp = last_bang.s;
if(changed && (n_psonce & n_PSO_INTERACTIVE))
fprintf(n_stdout, "!%s\n", cp);
}else
cp = cp_orig;
NYD_OU;
return cp;
--steffen
|
|Der Kragenbaer, The moon bear,
|der holt sich munter he cheerfully and one by one
|einen nach dem anderen runter wa.ks himself off
|(By Robert Gernhardt)
|~~
|..and in spring, hear David Leonard sing..
|
|The black bear, The black bear,
|blithely holds his own holds himself at leisure
|beating it, up and down tossing over his ups and downs with pleasure
|~~
|Farewell, dear collar bear
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