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#include "rc.h"
#include "parse.h"
#include "exec.h"
#include <signal.h>
#include <termios.h>
// -----------------------------------------------------------------------
// globals
Thread *runner = nil;
Shell shell = { 0 };
// -----------------------------------------------------------------------
// functions
void
initshell(int *iflag)
{
if((*iflag=isatty(0))){
while(tcgetpgrp(0) != (shell.pid = getpgrp()))
kill(-shell.pid, SIGTTIN);
/* ignore job control signals */
signal(SIGINT, SIG_IGN);
signal(SIGQUIT, SIG_IGN);
signal(SIGTSTP, SIG_IGN);
signal(SIGTTIN, SIG_IGN);
signal(SIGTTOU, SIG_IGN);
/* NOTE: if SIGCHLD is set to SIG_IGN then
* 1. children that terminate do not become zombies
* 2. call a to wait() will block until all children have terminated
* 3. the call to wait will fail with errno == ECHILD
* see for discussion:
* https://stackoverflow.com/questions/1608017/no-child-process-error-from-waitpid-when-waiting-for-process-group
*/
// signal(SIGCHLD, SIG_IGN);
/* take control */
shell.pid = getpid();
if(setpgid(shell.pid, shell.pid)<0)
fatal("could not put shell in its own process group");
tcsetpgrp(shell.pid, shell.pid);
}
}
// -----------------------------------------------------------------------
// main point of entry
static void
usage(void)
{
print(shell.err, "usage: %s [-cei] [file]", argv0);
exit(2);
}
int
main(int argc, char *argv[])
{
int flag;
char *exe, *cmd = nil;
shell.err = openfd(2);
initenv();
initpath();
initkeywords();
inithistory();
initshell(&flag);
ARGBEGIN{
case 'e': shell.noerror = 1; break;
case 'i': shell.interactive = 1; break;
case 'I': shell.interactive = 0; break;
case 'c':
cmd = EARGF(usage());
panicf("not implemented");
break;
default:
usage();
}ARGEND;
if(!argc){
shell.interactive |= flag;
exe = "/dev/stdin";
}else
exe = *argv++, argc--;
initlexer(shell.interactive);
/* enablevi(); */
xboot(exe, argc, argv);
/* unreachable */
}
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