Hi,
Whenever I use cu(1) I miss the possibility to configure the escape
character. Both ssh(1) and telnet(1) provide the option -e to change the
escape character.
So I created the diffs below to implement it. I think it's time to share
it with you and ask for your feedback.
Cheers,
Bruno
Index: usr.bin/cu/command.c
===================================================================
RCS file: /cvs/src/usr.bin/cu/command.c,v
retrieving revision 1.15
diff -u -p -r1.15 command.c
--- usr.bin/cu/command.c 5 Oct 2015 23:15:31 -0000 1.15
+++ usr.bin/cu/command.c 3 Aug 2017 08:54:38 -0000
@@ -219,9 +219,29 @@ start_record(void)
cu_warnx("%s", file);
}
+struct escape_help_text {
+ const char *cmd;
+ const char *text;
+};
+
+static struct escape_help_text esc_txt[] = {
+ {".", "drop connection and exit"},
+ {"#", "send break"},
+ {"$", "pipe local command to remote host"},
+ {">", "send file to remote host"},
+ {"C", "connect program to remote host"},
+ {"D", "de-assert DTR line briefly"},
+ {"R", "start recording to file"},
+ {"S", "set speed"},
+ {"X", "send file with XMODEM"},
+ {"?", "get this summary"},
+};
+
void
do_command(char c)
{
+ int i;
+
switch (c) {
case '.':
case '\004': /* ^D */
@@ -260,21 +280,15 @@ do_command(char c)
sleep(1);
ioctl(line_fd, TIOCCBRK, NULL);
break;
- case '~':
- bufferevent_write(line_ev, "~", 1);
- break;
case '?':
- printf("\r\n"
- "~# send break\r\n"
- "~$ pipe local command to remote host\r\n"
- "~> send file to remote host\r\n"
- "~C connect program to remote host\r\n"
- "~D de-assert DTR line briefly\r\n"
- "~R start recording to file\r\n"
- "~S set speed\r\n"
- "~X send file with XMODEM\r\n"
- "~? get this summary\r\n"
- );
+ for (i = 0; i < sizeof(esc_txt) / sizeof(esc_txt[0]); i++) {
+ if (escape < 32)
+ printf("\r\n^%c", escape + 64);
+ else
+ printf("\r\n%c", escape);
+ printf("%s\t%s", esc_txt[i].cmd, esc_txt[i].text);
+ }
+ printf("\r\n");
break;
}
}
Index: usr.bin/cu/cu.1
===================================================================
RCS file: /cvs/src/usr.bin/cu/cu.1,v
retrieving revision 1.15
diff -u -p -r1.15 cu.1
--- usr.bin/cu/cu.1 18 May 2015 09:35:05 -0000 1.15
+++ usr.bin/cu/cu.1 11 May 2017 11:56:15 -0000
@@ -36,6 +36,7 @@
.Sh SYNOPSIS
.Nm
.Op Fl d
+.Op Fl e Ar char
.Op Fl l Ar line
.Op Fl s Ar speed | Fl Ar speed
.Nm
@@ -55,6 +56,13 @@ The options are as follows:
Specify that the line is directly connected and
.Nm
should not allow the driver to block waiting for a carrier to be detected.
+.It Fl e Ar char
+Sets the
+.Nm
+escape character to
+.Pa char .
+If not specified the escape character is the tilde
+.Pq Ql ~ .
.It Fl l Ar line
Specify the line to use.
Either of the forms like
@@ -95,8 +103,8 @@ utility ignores other capabilities found
.Pp
Typed characters are normally transmitted directly to the remote
machine (which does the echoing as well).
-A tilde
-.Pq Ql ~
+The escape character (by default:
+.Ql ~ )
appearing as the first character of a line is an escape signal; the
following are recognized:
.Bl -tag -offset indent -width Fl
Index: usr.bin/cu/cu.c
===================================================================
RCS file: /cvs/src/usr.bin/cu/cu.c,v
retrieving revision 1.24
diff -u -p -r1.24 cu.c
--- usr.bin/cu/cu.c 16 Oct 2015 07:01:53 -0000 1.24
+++ usr.bin/cu/cu.c 3 Aug 2017 08:54:54 -0000
@@ -41,6 +41,7 @@ FILE *record_file;
struct termios saved_tio;
struct bufferevent *input_ev;
struct bufferevent *output_ev;
+u_char escape = '~';
int is_direct = -1;
const char *line_path = NULL;
int line_speed = -1;
@@ -52,7 +53,7 @@ struct event sighup_ev;
enum {
STATE_NONE,
STATE_NEWLINE,
- STATE_TILDE
+ STATE_ESCAPE
} last_state = STATE_NEWLINE;
__dead void usage(void);
@@ -66,7 +67,7 @@ void try_remote(const char *, const cha
__dead void
usage(void)
{
- fprintf(stderr, "usage: %s [-d] [-l line] [-s speed | -speed]\n",
+ fprintf(stderr, "usage: %s [-d] [-e char] [-l line] [-s speed |
-speed]\n",
__progname);
fprintf(stderr, " %s [host]\n", __progname);
exit(1);
@@ -100,11 +101,21 @@ main(int argc, char **argv)
errx(1, "speed asprintf");
}
- while ((opt = getopt(argc, argv, "dl:s:")) != -1) {
+ while ((opt = getopt(argc, argv, "de:l:s:")) != -1) {
switch (opt) {
case 'd':
is_direct = 1;
break;
+ case 'e':
+ if (optarg[0] == '^' && optarg[2] == 0 &&
+ (u_char) optarg[1] >= 64 &&
+ (u_char) optarg[1] < 128)
+ escape = (u_char) optarg[1] & 31;
+ else if (strlen(optarg) == 1)
+ escape = (u_char) optarg[0];
+ else
+ errx(1, "bad escape character '%s'", optarg);
+ break;
case 'l':
line_path = optarg;
break;
@@ -298,15 +309,18 @@ stream_read(struct bufferevent *bufev, v
last_state = STATE_NEWLINE;
break;
case STATE_NEWLINE:
- if (state_change && *ptr == '~') {
- last_state = STATE_TILDE;
+ if (state_change && *ptr == escape) {
+ last_state = STATE_ESCAPE;
continue;
}
if (*ptr != '\r')
last_state = STATE_NONE;
break;
- case STATE_TILDE:
- do_command(*ptr);
+ case STATE_ESCAPE:
+ if (*ptr == escape)
+ bufferevent_write(line_ev, ptr, 1);
+ else
+ do_command(*ptr);
last_state = STATE_NEWLINE;
continue;
}
Index: usr.bin/cu/cu.h
===================================================================
RCS file: /cvs/src/usr.bin/cu/cu.h,v
retrieving revision 1.7
diff -u -p -r1.7 cu.h
--- usr.bin/cu/cu.h 5 Oct 2015 23:15:31 -0000 1.7
+++ usr.bin/cu/cu.h 11 May 2017 11:18:45 -0000
@@ -25,6 +25,7 @@ void do_command(char);
/* cu.c */
extern FILE *record_file;
extern struct termios saved_tio;
+extern char escape;
extern int line_fd;
extern struct bufferevent *line_ev;
void set_blocking(int, int);
