NetBSD/bin/ksh/c_sh.c

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/* $NetBSD: c_sh.c,v 1.4 2001/02/04 19:26:04 christos Exp $ */
1997-01-12 22:11:37 +03:00
1996-09-22 03:35:13 +04:00
/*
* built-in Bourne commands
*/
#include "sh.h"
#include "ksh_stat.h" /* umask() */
#include "ksh_time.h"
#include "ksh_times.h"
static char *clocktos ARGS((clock_t t));
extern clock_t j_usrtime, j_systime; /* computed by j_wait */
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/* :, false and true */
int
c_label(wp)
char **wp;
{
return wp[0][0] == 'f' ? 1 : 0;
}
int
c_shift(wp)
char **wp;
{
register struct block *l = e->loc;
register int n;
long val;
char *arg;
if (ksh_getopt(wp, &builtin_opt, null) == '?')
return 1;
arg = wp[builtin_opt.optind];
if (arg) {
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evaluate(arg, &val, KSH_UNWIND_ERROR);
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n = val;
} else
n = 1;
if (n < 0) {
bi_errorf("%s: bad number", arg);
return (1);
}
if (l->argc < n) {
bi_errorf("nothing to shift");
return (1);
}
l->argv[n] = l->argv[0];
l->argv += n;
l->argc -= n;
return 0;
}
int
c_umask(wp)
char **wp;
{
register int i;
register char *cp;
int symbolic = 0;
int old_umask;
int optc;
while ((optc = ksh_getopt(wp, &builtin_opt, "S")) != EOF)
switch (optc) {
case 'S':
symbolic = 1;
break;
case '?':
return 1;
}
cp = wp[builtin_opt.optind];
if (cp == NULL) {
old_umask = umask(0);
umask(old_umask);
if (symbolic) {
char buf[18];
int j;
old_umask = ~old_umask;
cp = buf;
for (i = 0; i < 3; i++) {
*cp++ = "ugo"[i];
*cp++ = '=';
for (j = 0; j < 3; j++)
if (old_umask & (1 << (8 - (3*i + j))))
*cp++ = "rwx"[j];
*cp++ = ',';
}
cp[-1] = '\0';
shprintf("%s\n", buf);
} else
shprintf("%#3.3o\n", old_umask);
} else {
int new_umask;
if (digit(*cp)) {
for (new_umask = 0; *cp >= '0' && *cp <= '7'; cp++)
new_umask = new_umask * 8 + (*cp - '0');
if (*cp) {
bi_errorf("bad number");
return 1;
}
} else {
/* symbolic format */
int positions, new_val;
char op;
old_umask = umask(0);
umask(old_umask); /* in case of error */
old_umask = ~old_umask;
new_umask = old_umask;
positions = 0;
while (*cp) {
while (*cp && strchr("augo", *cp))
switch (*cp++) {
case 'a': positions |= 0111; break;
case 'u': positions |= 0100; break;
case 'g': positions |= 0010; break;
case 'o': positions |= 0001; break;
}
if (!positions)
positions = 0111; /* default is a */
if (!strchr("=+-", op = *cp))
break;
cp++;
new_val = 0;
while (*cp && strchr("rwxugoXs", *cp))
switch (*cp++) {
case 'r': new_val |= 04; break;
case 'w': new_val |= 02; break;
case 'x': new_val |= 01; break;
case 'u': new_val |= old_umask >> 6;
break;
case 'g': new_val |= old_umask >> 3;
break;
case 'o': new_val |= old_umask >> 0;
break;
case 'X': if (old_umask & 0111)
new_val |= 01;
break;
case 's': /* ignored */
break;
}
new_val = (new_val & 07) * positions;
switch (op) {
case '-':
new_umask &= ~new_val;
break;
case '=':
new_umask = new_val
| (new_umask & ~(positions * 07));
break;
case '+':
new_umask |= new_val;
}
if (*cp == ',') {
positions = 0;
cp++;
} else if (!strchr("=+-", *cp))
break;
}
if (*cp) {
bi_errorf("bad mask");
return 1;
}
new_umask = ~new_umask;
}
umask(new_umask);
}
return 0;
}
int
c_dot(wp)
char **wp;
{
char *file, *cp;
char **argv;
int argc;
int i;
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int err;
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if (ksh_getopt(wp, &builtin_opt, null) == '?')
return 1;
if ((cp = wp[builtin_opt.optind]) == NULL)
return 0;
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file = search(cp, path, R_OK, &err);
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if (file == NULL) {
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bi_errorf("%s: %s", cp, err ? strerror(err) : "not found");
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return 1;
}
/* Set positional parameters? */
if (wp[builtin_opt.optind + 1]) {
argv = wp + builtin_opt.optind;
argv[0] = e->loc->argv[0]; /* preserve $0 */
for (argc = 0; argv[argc + 1]; argc++)
;
} else {
argc = 0;
argv = (char **) 0;
}
i = include(file, argc, argv, 0);
if (i < 0) { /* should not happen */
bi_errorf("%s: %s", cp, strerror(errno));
return 1;
}
return i;
}
int
c_wait(wp)
char **wp;
{
int UNINITIALIZED(rv);
int sig;
if (ksh_getopt(wp, &builtin_opt, null) == '?')
return 1;
wp += builtin_opt.optind;
if (*wp == (char *) 0) {
while (waitfor((char *) 0, &sig) >= 0)
;
rv = sig;
} else {
for (; *wp; wp++)
rv = waitfor(*wp, &sig);
if (rv < 0)
rv = sig ? sig : 127; /* magic exit code: bad job-id */
}
return rv;
}
int
c_read(wp)
char **wp;
{
register int c = 0;
int expand = 1, history = 0;
int expanding;
int ecode = 0;
register char *cp;
int fd = 0;
struct shf *shf;
int optc;
const char *emsg;
XString cs, xs;
struct tbl *vp;
char UNINITIALIZED(*xp);
while ((optc = ksh_getopt(wp, &builtin_opt, "prsu,")) != EOF)
switch (optc) {
#ifdef KSH
case 'p':
if ((fd = coproc_getfd(R_OK, &emsg)) < 0) {
bi_errorf("-p: %s", emsg);
return 1;
}
break;
#endif /* KSH */
case 'r':
expand = 0;
break;
case 's':
history = 1;
break;
case 'u':
if (!*(cp = builtin_opt.optarg))
fd = 0;
else if ((fd = check_fd(cp, R_OK, &emsg)) < 0) {
bi_errorf("-u: %s: %s", cp, emsg);
return 1;
}
break;
case '?':
return 1;
}
wp += builtin_opt.optind;
if (*wp == NULL)
*--wp = "REPLY";
/* Since we can't necessarily seek backwards on non-regular files,
* don't buffer them so we can't read too much.
*/
shf = shf_reopen(fd, SHF_RD | SHF_INTERRUPT | can_seek(fd), shl_spare);
if ((cp = strchr(*wp, '?')) != NULL) {
*cp = 0;
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if (isatty(fd)) {
/* at&t ksh says it prints prompt on fd if it's open
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* for writing and is a tty, but it doesn't do it
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* (it also doesn't check the interactive flag,
* as is indicated in the Kornshell book).
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*/
shellf("%s", cp+1);
}
}
#ifdef KSH
/* If we are reading from the co-process for the first time,
* make sure the other side of the pipe is closed first. This allows
* the detection of eof.
*
* This is not compatiable with at&t ksh... the fd is kept so another
* coproc can be started with same ouput, however, this means eof
* can't be detected... This is why it is closed here.
* If this call is removed, remove the eof check below, too.
* coproc_readw_close(fd);
*/
#endif /* KSH */
if (history)
Xinit(xs, xp, 128, ATEMP);
expanding = 0;
Xinit(cs, cp, 128, ATEMP);
for (; *wp != NULL; wp++) {
for (cp = Xstring(cs, cp); ; ) {
if (c == '\n' || c == EOF)
break;
while (1) {
c = shf_getc(shf);
if (c == '\0'
#ifdef OS2
|| c == '\r'
#endif /* OS2 */
)
continue;
if (c == EOF && shf_error(shf)
&& shf_errno(shf) == EINTR)
{
/* Was the offending signal one that
* would normally kill a process?
* If so, pretend the read was killed.
*/
ecode = fatal_trap_check();
/* non fatal (eg, CHLD), carry on */
if (!ecode) {
shf_clearerr(shf);
continue;
}
}
break;
}
if (history) {
Xcheck(xs, xp);
Xput(xs, xp, c);
}
Xcheck(cs, cp);
if (expanding) {
expanding = 0;
if (c == '\n') {
c = 0;
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if (Flag(FTALKING_I) && isatty(fd)) {
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/* set prompt in case this is
* called from .profile or $ENV
*/
set_prompt(PS2, (Source *) 0);
pprompt(prompt, 0);
}
} else if (c != EOF)
Xput(cs, cp, c);
continue;
}
if (expand && c == '\\') {
expanding = 1;
continue;
}
if (c == '\n' || c == EOF)
break;
if (ctype(c, C_IFS)) {
if (Xlength(cs, cp) == 0 && ctype(c, C_IFSWS))
continue;
if (wp[1])
break;
}
Xput(cs, cp, c);
}
/* strip trailing IFS white space from last variable */
if (!wp[1])
while (Xlength(cs, cp) && ctype(cp[-1], C_IFS)
&& ctype(cp[-1], C_IFSWS))
cp--;
Xput(cs, cp, '\0');
vp = global(*wp);
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/* Must be done before setting export. */
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if (vp->flag & RDONLY) {
shf_flush(shf);
bi_errorf("%s is read only", *wp);
return 1;
}
if (Flag(FEXPORT))
typeset(*wp, EXPORT, 0, 0, 0);
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if (!setstr(vp, Xstring(cs, cp), KSH_RETURN_ERROR)) {
shf_flush(shf);
return 1;
}
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}
shf_flush(shf);
if (history) {
Xput(xs, xp, '\0');
source->line++;
histsave(source->line, Xstring(xs, xp), 1);
Xfree(xs, xp);
}
#ifdef KSH
/* if this is the co-process fd, close the file descriptor
* (can get eof if and only if all processes are have died, ie,
* coproc.njobs is 0 and the pipe is closed).
*/
if (c == EOF && !ecode)
coproc_read_close(fd);
#endif /* KSH */
return ecode ? ecode : c == EOF;
}
int
c_eval(wp)
char **wp;
{
register struct source *s;
if (ksh_getopt(wp, &builtin_opt, null) == '?')
return 1;
s = pushs(SWORDS, ATEMP);
s->u.strv = wp + builtin_opt.optind;
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if (!Flag(FPOSIX)) {
/*
* Handle case where the command is empty due to failed
* command substitution, eg, eval "$(false)".
* In this case, shell() will not set/change exstat (because
* compiled tree is empty), so will use this value.
* subst_exstat is cleared in execute(), so should be 0 if
* there were no substitutions.
*
* A strict reading of POSIX says we don't do this (though
* it is traditionally done). [from 1003.2-1992]
* 3.9.1: Simple Commands
* ... If there is a command name, execution shall
* continue as described in 3.9.1.1. If there
* is no command name, but the command contained a command
* substitution, the command shall complete with the exit
* status of the last command substitution
* 3.9.1.1: Command Search and Execution
* ...(1)...(a) If the command name matches the name of
* a special built-in utility, that special built-in
* utility shall be invoked.
* 3.14.5: Eval
* ... If there are no arguments, or only null arguments,
* eval shall return an exit status of zero.
*/
exstat = subst_exstat;
}
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return shell(s, FALSE);
}
int
c_trap(wp)
char **wp;
{
int i;
char *s;
register Trap *p;
if (ksh_getopt(wp, &builtin_opt, null) == '?')
return 1;
wp += builtin_opt.optind;
if (*wp == NULL) {
int anydfl = 0;
for (p = sigtraps, i = SIGNALS+1; --i >= 0; p++) {
if (p->trap == NULL)
anydfl = 1;
else {
shprintf("trap -- ");
print_value_quoted(p->trap);
shprintf(" %s\n", p->name);
}
}
#if 0 /* this is ugly and not clear POSIX needs it */
/* POSIX may need this so output of trap can be saved and
* used to restore trap conditions
*/
if (anydfl) {
shprintf("trap -- -");
for (p = sigtraps, i = SIGNALS+1; --i >= 0; p++)
if (p->trap == NULL && p->name)
shprintf(" %s", p->name);
shprintf(newline);
}
#endif
return 0;
}
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/*
* Use case sensitive lookup for first arg so the
* command 'exit' isn't confused with the pseudo-signal
* 'EXIT'.
*/
s = (gettrap(*wp, FALSE) == NULL) ? *wp++ : NULL; /* get command */
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if (s != NULL && s[0] == '-' && s[1] == '\0')
s = NULL;
/* set/clear traps */
while (*wp != NULL) {
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p = gettrap(*wp++, TRUE);
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if (p == NULL) {
bi_errorf("bad signal %s", wp[-1]);
return 1;
}
settrap(p, s);
}
return 0;
}
int
c_exitreturn(wp)
char **wp;
{
int how = LEXIT;
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int n;
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char *arg;
if (ksh_getopt(wp, &builtin_opt, null) == '?')
return 1;
arg = wp[builtin_opt.optind];
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if (arg) {
if (!getn(arg, &n)) {
exstat = 1;
warningf(TRUE, "%s: bad number", arg);
} else
exstat = n;
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}
if (wp[0][0] == 'r') { /* return */
struct env *ep;
/* need to tell if this is exit or return so trap exit will
* work right (POSIX)
*/
for (ep = e; ep; ep = ep->oenv)
if (STOP_RETURN(ep->type)) {
how = LRETURN;
break;
}
}
if (how == LEXIT && !really_exit && j_stopped_running()) {
really_exit = 1;
how = LSHELL;
}
quitenv(); /* get rid of any i/o redirections */
unwind(how);
/*NOTREACHED*/
return 0;
}
int
c_brkcont(wp)
char **wp;
{
int n, quit;
struct env *ep, *last_ep = (struct env *) 0;
char *arg;
if (ksh_getopt(wp, &builtin_opt, null) == '?')
return 1;
arg = wp[builtin_opt.optind];
if (!arg)
n = 1;
else if (!bi_getn(arg, &n))
return 1;
quit = n;
if (quit <= 0) {
/* at&t ksh does this for non-interactive shells only - weird */
bi_errorf("%s: bad value", arg);
return 1;
}
/* Stop at E_NONE, E_PARSE, E_FUNC, or E_INCL */
for (ep = e; ep && !STOP_BRKCONT(ep->type); ep = ep->oenv)
if (ep->type == E_LOOP) {
if (--quit == 0)
break;
ep->flags |= EF_BRKCONT_PASS;
last_ep = ep;
}
if (quit) {
/* at&t ksh doesn't print a message - just does what it
* can. We print a message 'cause it helps in debugging
* scripts, but don't generate an error (ie, keep going).
*/
if (n == quit) {
warningf(TRUE, "%s: cannot %s", wp[0], wp[0]);
return 0;
}
/* POSIX says if n is too big, the last enclosing loop
* shall be used. Doesn't say to print an error but we
* do anyway 'cause the user messed up.
*/
last_ep->flags &= ~EF_BRKCONT_PASS;
warningf(TRUE, "%s: can only %s %d level(s)",
wp[0], wp[0], n - quit);
}
unwind(*wp[0] == 'b' ? LBREAK : LCONTIN);
/*NOTREACHED*/
}
int
c_set(wp)
char **wp;
{
int argi, setargs;
struct block *l = e->loc;
register char **owp = wp;
if (wp[1] == NULL) {
static const char *const args [] = { "set", "-", NULL };
return c_typeset((char **) args);
}
argi = parse_args(wp, OF_SET, &setargs);
if (argi < 0)
return 1;
/* set $# and $* */
if (setargs) {
owp = wp += argi - 1;
wp[0] = l->argv[0]; /* save $0 */
while (*++wp != NULL)
*wp = str_save(*wp, &l->area);
l->argc = wp - owp - 1;
l->argv = (char **) alloc(sizeofN(char *, l->argc+2), &l->area);
for (wp = l->argv; (*wp++ = *owp++) != NULL; )
;
}
/* POSIX says set exit status is 0, but old scripts that use
* getopt(1), use the construct: set -- `getopt ab:c "$@"`
* which assumes the exit value set will be that of the ``
* (subst_exstat is cleared in execute() so that it will be 0
* if there are no command substitutions).
*/
return Flag(FPOSIX) ? 0 : subst_exstat;
}
int
c_unset(wp)
char **wp;
{
register char *id;
int optc, unset_var = 1;
int ret = 0;
while ((optc = ksh_getopt(wp, &builtin_opt, "fv")) != EOF)
switch (optc) {
case 'f':
unset_var = 0;
break;
case 'v':
unset_var = 1;
break;
case '?':
return 1;
}
wp += builtin_opt.optind;
for (; (id = *wp) != NULL; wp++)
if (unset_var) { /* unset variable */
struct tbl *vp = global(id);
if (!(vp->flag & ISSET))
ret = 1;
if ((vp->flag&RDONLY)) {
bi_errorf("%s is read only", vp->name);
return 1;
}
unset(vp, strchr(id, '[') ? 1 : 0);
} else { /* unset function */
if (define(id, (struct op *) NULL))
ret = 1;
}
return ret;
}
int
c_times(wp)
char **wp;
{
struct tms all;
(void) ksh_times(&all);
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shprintf("Shell: %8ss user ", clocktos(all.tms_utime));
shprintf("%8ss system\n", clocktos(all.tms_stime));
shprintf("Kids: %8ss user ", clocktos(all.tms_cutime));
shprintf("%8ss system\n", clocktos(all.tms_cstime));
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return 0;
}
/*
* time pipeline (really a statement, not a built-in command)
*/
int
timex(t, f)
struct op *t;
int f;
{
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#define TF_NOARGS BIT(0)
#define TF_NOREAL BIT(1) /* don't report real time */
#define TF_POSIX BIT(2) /* report in posix format */
int rv = 0;
struct tms t0, t1, tms;
clock_t t0t, t1t = 0;
int tf = 0;
char opts[1];
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t0t = ksh_times(&t0);
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if (t->left) {
/*
* Two ways of getting cpu usage of a command: just use t0
* and t1 (which will get cpu usage from other jobs that
* finish while we are executing t->left), or get the
* cpu usage of t->left. at&t ksh does the former, while
* pdksh tries to do the later (the j_usrtime hack doesn't
* really work as it only counts the last job).
*/
j_usrtime = j_systime = 0;
if (t->left->type == TCOM)
t->left->str = opts;
opts[0] = 0;
rv = execute(t->left, f | XTIME);
tf |= opts[0];
t1t = ksh_times(&t1);
} else
tf = TF_NOARGS;
if (tf & TF_NOARGS) { /* ksh93 - report shell times (shell+kids) */
tf |= TF_NOREAL;
tms.tms_utime = t0.tms_utime + t0.tms_cutime;
tms.tms_stime = t0.tms_stime + t0.tms_cstime;
} else {
tms.tms_utime = t1.tms_utime - t0.tms_utime + j_usrtime;
tms.tms_stime = t1.tms_stime - t0.tms_stime + j_systime;
}
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if (!(tf & TF_NOREAL))
shf_fprintf(shl_out,
tf & TF_POSIX ? "real %8s\n" : "%8ss real ",
clocktos(t1t - t0t));
shf_fprintf(shl_out, tf & TF_POSIX ? "user %8s\n" : "%8ss user ",
clocktos(tms.tms_utime));
shf_fprintf(shl_out, tf & TF_POSIX ? "sys %8s\n" : "%8ss system\n",
clocktos(tms.tms_stime));
shf_flush(shl_out);
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return rv;
}
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void
timex_hook(t, app)
struct op *t;
char ** volatile *app;
{
char **wp = *app;
int optc;
int i, j;
Getopt opt;
ksh_getopt_reset(&opt, 0);
opt.optind = 0; /* start at the start */
while ((optc = ksh_getopt(wp, &opt, ":p")) != EOF)
switch (optc) {
case 'p':
t->str[0] |= TF_POSIX;
break;
case '?':
errorf("time: -%s unknown option", opt.optarg);
case ':':
errorf("time: -%s requires an argument",
opt.optarg);
}
/* Copy command words down over options. */
if (opt.optind != 0) {
for (i = 0; i < opt.optind; i++)
afree(wp[i], ATEMP);
for (i = 0, j = opt.optind; (wp[i] = wp[j]); i++, j++)
;
}
if (!wp[0])
t->str[0] |= TF_NOARGS;
*app = wp;
}
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static char *
clocktos(t)
clock_t t;
{
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static char temp[22]; /* enough for 64 bit clock_t */
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register int i;
register char *cp = temp + sizeof(temp);
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/* note: posix says must use max precision, ie, if clk_tck is
* 1000, must print 3 places after decimal (if non-zero, else 1).
*/
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if (CLK_TCK != 100) /* convert to 1/100'ths */
t = (t < 1000000000/CLK_TCK) ?
(t * 100) / CLK_TCK : (t / CLK_TCK) * 100;
*--cp = '\0';
for (i = -2; i <= 0 || t > 0; i++) {
if (i == 0)
*--cp = '.';
*--cp = '0' + (char)(t%10);
t /= 10;
}
return cp;
}
/* exec with no args - args case is taken care of in comexec() */
int
c_exec(wp)
char ** wp;
{
int i;
/* make sure redirects stay in place */
if (e->savefd != NULL) {
for (i = 0; i < NUFILE; i++) {
if (e->savefd[i] > 0)
close(e->savefd[i]);
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/*
* For ksh keep anything > 2 private,
* for sh, let them be (POSIX says what
* happens is unspecified and the bourne shell
* keeps them open).
*/
#ifdef KSH
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if (i > 2 && e->savefd[i])
fd_clexec(i);
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#endif /* KSH */
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}
e->savefd = NULL;
}
return 0;
}
/* dummy function, special case in comexec() */
int
c_builtin(wp)
char ** wp;
{
return 0;
}
/* A leading = means assignments before command are kept;
* a leading * means a POSIX special builtin;
* a leading + means a POSIX regular builtin
* (* and + should not be combined).
*/
const struct builtin shbuiltins [] = {
{"*=.", c_dot},
{"*=:", c_label},
{"[", c_test},
{"*=break", c_brkcont},
{"=builtin", c_builtin},
{"*=continue", c_brkcont},
{"*=eval", c_eval},
{"*=exec", c_exec},
{"*=exit", c_exitreturn},
{"+false", c_label},
{"*=return", c_exitreturn},
{"*=set", c_set},
{"*=shift", c_shift},
{"=times", c_times},
{"*=trap", c_trap},
{"+=wait", c_wait},
{"+read", c_read},
{"test", c_test},
{"+true", c_label},
{"ulimit", c_ulimit},
{"+umask", c_umask},
{"*=unset", c_unset},
#ifdef OS2
/* In OS2, the first line of a file can be "extproc name", which
* tells the command interpreter (cmd.exe) to use name to execute
* the file. For this to be useful, ksh must ignore commands
* starting with extproc and this does the trick...
*/
{"extproc", c_label},
#endif /* OS2 */
{NULL, NULL}
};