int
main(int argc, char *argv[])
{
char ch;
struct sigaction sa, prev;
ssize_t n;
sigemptyset(&sa.sa_mask);
sa.sa_flags = SA_RESTART;
if (argc > 1) { /* Use cbreak mode */
if (ttySetCbreak(STDIN_FILENO, &userTermios) == -1)
errExit("ttySetCbreak");
/* Terminal special characters can generate signals in cbreak
mode. Catch them so that we can adjust the terminal mode.
We establish handlers only if the signals are not being ignored. */
sa.sa_handler = handler;
if (sigaction(SIGQUIT, NULL, &prev) == -1)
errExit("sigaction");
if (prev.sa_handler != SIG_IGN)
if (sigaction(SIGQUIT, &sa, NULL) == -1)
errExit("sigaction");
if (sigaction(SIGINT, NULL, &prev) == -1)
errExit("sigaction");
if (prev.sa_handler != SIG_IGN)
if (sigaction(SIGINT, &sa, NULL) == -1)
errExit("sigaction");
sa.sa_handler = tstpHandler;
if (sigaction(SIGTSTP, NULL, &prev) == -1)
errExit("sigaction");
if (prev.sa_handler != SIG_IGN)
if (sigaction(SIGTSTP, &sa, NULL) == -1)
errExit("sigaction");
} else { /* Use raw mode */
if (ttySetRaw(STDIN_FILENO, &userTermios) == -1)
errExit("ttySetRaw");
}
sa.sa_handler = handler;
if (sigaction(SIGTERM, &sa, NULL) == -1)
errExit("sigaction");
setbuf(stdout, NULL); /* Disable stdout buffering */
for (;;) { /* Read and echo stdin */
n = read(STDIN_FILENO, &ch, 1);
if (n == -1) {
errMsg("read");
break;
}
if (n == 0) /* Can occur after terminal disconnect */
break;
if (isalpha((unsigned char) ch)) /* Letters --> lowercase */
putchar(tolower((unsigned char) ch));
else if (ch == '\n' || ch == '\r')
putchar(ch);
else if (iscntrl((unsigned char) ch))
printf("^%c", ch ^ 64); /* Echo Control-A as ^A, etc. */
else
putchar('*'); /* All other chars as '*' */
if (ch == 'q') /* Quit loop */
break;
}
if (tcsetattr(STDIN_FILENO, TCSAFLUSH, &userTermios) == -1)
errExit("tcsetattr");
exit(EXIT_SUCCESS);
}
int
main(int argc, char *argv[])
{
char slaveName[MAX_SNAME];
int masterFd;
fd_set inFds;
char buf[BUF_SIZE];
ssize_t numRead;
struct winsize ws;
/* Retrieve the attributes of terminal on which we are started */
if (tcgetattr(STDIN_FILENO, &ttyOrig) == -1)
errExit("tcgetattr");
if (ioctl(STDIN_FILENO, TIOCGWINSZ, (char *) &ws) < 0)
errExit("TIOCGWINSZ error");
/* Create a child process, with parent and child connected via a
pty pair. The child is connected to the pty slave and its terminal
attributes are set to be the same as those retrieved above. */
switch (ptyFork(&masterFd, slaveName, MAX_SNAME, &ttyOrig, &ws)) {
case -1:
errExit("ptyFork");
case 0: /* Child executes command given in argv[1]... */
execvp(argv[1], &argv[1]);
errExit("execvp");
default: /* Parent relays data between terminal and pty master */
/* Place terminal in raw mode so that we can pass all
terminal input to the pseudoterminal master untouched */
ttySetRaw(STDIN_FILENO, &ttyOrig);
if (atexit(ttyReset) != 0)
errExit("atexit");
/* Loop monitoring terminal and pty master for input. If the
terminal is ready for input, read some bytes and write
them to the pty master. If the pty master is ready for
input, read some bytes and write them to the terminal. */
for (;;) {
FD_ZERO(&inFds);
FD_SET(STDIN_FILENO, &inFds);
FD_SET(masterFd, &inFds);
if (select(masterFd + 1, &inFds, NULL, NULL, NULL) == -1)
errExit("select");
if (FD_ISSET(STDIN_FILENO, &inFds)) {
numRead = read(STDIN_FILENO, buf, BUF_SIZE);
if (numRead <= 0)
exit(EXIT_SUCCESS);
if (write(masterFd, buf, numRead) != numRead)
fatal("partial/failed write (masterFd)");
}
if (FD_ISSET(masterFd, &inFds)) {
numRead = read(masterFd, buf, BUF_SIZE);
if (numRead <= 0)
exit(EXIT_SUCCESS);
if (write(STDOUT_FILENO, buf, numRead) != numRead)
fatal("partial/failed write (STDOUT_FILENO)");
}
}
}
}
int
main(int argc, char *argv[])
{
char slaveName[MAX_SNAME];
char *shell;
int masterFd, scriptFd;
struct winsize ws;
fd_set inFds;
char buf[BUF_SIZE];
ssize_t numRead;
pid_t childPid;
if (tcgetattr(STDIN_FILENO, &ttyOrig) == -1)
errExit("tcgetattr");
if (ioctl(STDIN_FILENO, TIOCGWINSZ, &ws) < 0)
errExit("ioctl-TIOCGWINSZ");
childPid = ptyFork(&masterFd, slaveName, MAX_SNAME, &ttyOrig, &ws);
if (childPid == -1)
errExit("ptyFork");
if (childPid == 0) { /* Child: execute a shell on pty slave */
shell = getenv("SHELL");
if (shell == NULL || *shell == '\0')
shell = "/bin/sh";
execlp(shell, shell, (char *) NULL);
errExit("execlp"); /* If we get here, something went wrong */
}
/* Parent: relay data between terminal and pty master */
scriptFd = open((argc > 1) ? argv[1] : "typescript",
O_WRONLY | O_CREAT | O_TRUNC,
S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP |
S_IROTH | S_IWOTH);
if (scriptFd == -1)
errExit("open typescript");
ttySetRaw(STDIN_FILENO, &ttyOrig);
if (atexit(ttyReset) != 0)
errExit("atexit");
for (;;) {
FD_ZERO(&inFds);
FD_SET(STDIN_FILENO, &inFds);
FD_SET(masterFd, &inFds);
if (select(masterFd + 1, &inFds, NULL, NULL, NULL) == -1)
errExit("select");
if (FD_ISSET(STDIN_FILENO, &inFds)) { /* stdin --> pty */
numRead = read(STDIN_FILENO, buf, BUF_SIZE);
if (numRead <= 0)
exit(EXIT_SUCCESS);
if (write(masterFd, buf, numRead) != numRead)
fatal("partial/failed write (masterFd)");
}
if (FD_ISSET(masterFd, &inFds)) { /* pty --> stdout+file */
numRead = read(masterFd, buf, BUF_SIZE);
if (numRead <= 0)
exit(EXIT_SUCCESS);
if (write(STDOUT_FILENO, buf, numRead) != numRead)
fatal("partial/failed write (STDOUT_FILENO)");
if (write(scriptFd, buf, numRead) != numRead)
fatal("partial/failed write (scriptFd)");
}
}
}
int
main(int argc, char *argv[])
{
char slaveName[MAX_SNAME];
char *shell;
int masterFd, scriptFd;
struct winsize ws;
fd_set inFds;
char buf[BUF_SIZE];
ssize_t numRead;
pid_t childPid;
/* Retrieve the attributes of terminal on which we are started */
if (tcgetattr(STDIN_FILENO, &ttyOrig) == -1)
errExit("tcgetattr");
if (ioctl(STDIN_FILENO, TIOCGWINSZ, &ws) < 0)
errExit("ioctl-TIOCGWINSZ");
/* Create a child process, with parent and child connected via a
pty pair. The child is connected to the pty slave and its terminal
attributes are set to be the same as those retrieved above. */
childPid = ptyFork(&masterFd, slaveName, MAX_SNAME, &ttyOrig, &ws);
if (childPid == -1)
errExit("ptyFork");
if (childPid == 0) { /* Child: execute a shell on pty slave */
/* If the SHELL variable is set, use its value to determine
the shell execed in child. Otherwise use /bin/sh. */
shell = getenv("SHELL");
if (shell == NULL || *shell == '\0')
shell = "/bin/sh";
execlp(shell, shell, (char *) NULL);
errExit("execlp"); /* If we get here, something went wrong */
}
/* Parent: relay data between terminal and pty master */
scriptFd = open((argc > 1) ? argv[1] : "typescript",
O_WRONLY | O_CREAT | O_TRUNC,
S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP |
S_IROTH | S_IWOTH);
if (scriptFd == -1)
errExit("open typescript");
/* Place terminal in raw mode so that we can pass all terminal
input to the pseudoterminal master untouched */
ttySetRaw(STDIN_FILENO, &ttyOrig);
if (atexit(ttyReset) != 0)
errExit("atexit");
/* Loop monitoring terminal and pty master for input. If the
terminal is ready for input, then read some bytes and write
them to the pty master. If the pty master is ready for input,
then read some bytes and write them to the terminal. */
for (;;) {
FD_ZERO(&inFds);
FD_SET(STDIN_FILENO, &inFds);
FD_SET(masterFd, &inFds);
if (select(masterFd + 1, &inFds, NULL, NULL, NULL) == -1)
errExit("select");
if (FD_ISSET(STDIN_FILENO, &inFds)) { /* stdin --> pty */
numRead = read(STDIN_FILENO, buf, BUF_SIZE);
if (numRead <= 0)
exit(EXIT_SUCCESS);
if (write(masterFd, buf, numRead) != numRead)
fatal("partial/failed write (masterFd)");
}
if (FD_ISSET(masterFd, &inFds)) { /* pty --> stdout+file */
numRead = read(masterFd, buf, BUF_SIZE);
if (numRead <= 0)
exit(EXIT_SUCCESS);
if (write(STDOUT_FILENO, buf, numRead) != numRead)
fatal("partial/failed write (STDOUT_FILENO)");
if (write(scriptFd, buf, numRead) != numRead)
fatal("partial/failed write (scriptFd)");
}
}
}