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/* open.c: to insulate <fcntl.h> from the rest of rc. */
#include "rc.h"
#include <fcntl.h>
/*
Opens a file with the necessary flags. Assumes the following
declaration for redirtype:
enum redirtype {
rFrom, rCreate, rAppend, rHeredoc, rHerestring
};
*/
static const int mode_masks[] = {
/* rFrom */ O_RDONLY,
/* rCreate */ O_TRUNC | O_CREAT | O_WRONLY,
/* rAppend */ O_APPEND | O_CREAT | O_WRONLY
};
extern int rc_open(const char *name, redirtype m) {
if ((unsigned) m >= arraysize(mode_masks))
panic("bad mode passed to rc_open");
return open(name, mode_masks[m], 0666);
}
/* make a file descriptor blocking. return value indicates whether
the desciptor was previously set to non-blocking. */
extern bool makeblocking(int fd) {
int flags;
if ((flags = fcntl(fd, F_GETFL)) == -1) {
uerror("fcntl");
rc_error(NULL);
}
if (! (flags & O_NONBLOCK))
return FALSE;
flags &= ~O_NONBLOCK;
if (fcntl(fd, F_SETFL, (long) flags) == -1) {
uerror("fcntl");
rc_error(NULL);
}
return TRUE;
}
/* make a file descriptor the same pgrp as us. Returns TRUE if
it changes anything. */
extern bool makesamepgrp(int fd) {
pid_t grp;
grp = getpgrp();
if (tcgetpgrp(fd) == grp)
return FALSE;
if (tcsetpgrp(fd, grp) < 0) {
uerror("tcsetgrp");
return FALSE;
}
return TRUE;
}
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