diff options
-rw-r--r-- | erts/doc/src/run_erl.xml | 8 | ||||
-rw-r--r-- | erts/etc/unix/run_erl.c | 21 |
2 files changed, 27 insertions, 2 deletions
diff --git a/erts/doc/src/run_erl.xml b/erts/doc/src/run_erl.xml index 7bf7f559c5..da08859c7b 100644 --- a/erts/doc/src/run_erl.xml +++ b/erts/doc/src/run_erl.xml @@ -144,6 +144,14 @@ <item>The size (in bytes) of a log file before switching to a new log file. Default is 100000, minimum is 1000 and maximum is approximately 2^30.</item> + <tag>RUN_ERL_DISABLE_FLOWCNTRL</tag> + <item>If defined, disables input and output flow control for the pty opend by run_erl. + Useful if you want to remove any risk of accidentally blocking the flow control + by hit Ctrl-S (instead of Ctrl-D to detach). + Which may result in blocking of the entire beam process + and in the case of running heart as supervisor + even the heart process will be blocked when writing log message to terminal. + Leaving the heart process unable to do its work.</item> </taglist> </section> diff --git a/erts/etc/unix/run_erl.c b/erts/etc/unix/run_erl.c index e97cc14fab..8db8e09bee 100644 --- a/erts/etc/unix/run_erl.c +++ b/erts/etc/unix/run_erl.c @@ -991,9 +991,7 @@ static int open_pty_master(char **ptyslave) static int open_pty_slave(char *name) { int sfd; -#ifdef DEBUG struct termios tty_rmode; -#endif if ((sfd = open(name, O_RDWR, 0)) < 0) { return -1; @@ -1019,6 +1017,25 @@ static int open_pty_slave(char *name) } #endif + if (getenv("RUN_ERL_DISABLE_FLOWCNTRL")) { + if (tcgetattr(sfd, &tty_rmode) < 0) { + fprintf(stderr, "Cannot get terminal's current mode\n"); + exit(-1); + } + + tty_rmode.c_iflag &= ~IXOFF; + if (tcsetattr(sfd, TCSANOW, &tty_rmode) < 0) { + fprintf(stderr, "Cannot disable terminal's flow control on input\n"); + exit(-1); + } + + tty_rmode.c_iflag &= ~IXON; + if (tcsetattr(sfd, TCSANOW, &tty_rmode) < 0) { + fprintf(stderr, "Cannot disable terminal's flow control on output\n"); + exit(-1); + } + } + #ifdef DEBUG if (tcgetattr(sfd, &tty_rmode) < 0) { fprintf(stderr, "Cannot get terminals current mode\n"); |