diff options
Diffstat (limited to 'toys/other/netcat.c')
| -rw-r--r-- | toys/other/netcat.c | 30 |
1 files changed, 14 insertions, 16 deletions
diff --git a/toys/other/netcat.c b/toys/other/netcat.c index 0173e6db..a245d119 100644 --- a/toys/other/netcat.c +++ b/toys/other/netcat.c @@ -11,13 +11,13 @@ config NETCAT bool "netcat" default y help - usage: netcat [-wpq #] [-s addr] {IPADDR PORTNUM|-f FILENAME|-let} [-e COMMAND] + usage: netcat [-wpq #] [-s addr] [-u] {IPADDR PORTNUM|-f FILENAME} - -w SECONDS timeout for connection + -f use FILENAME (ala /dev/ttyS0) instead of network -p local port number - -s local ipv4 address -q SECONDS quit this many seconds after EOF on stdin. - -f use FILENAME (ala /dev/ttyS0) instead of network + -s local ipv4 address + -w SECONDS timeout for connection Use "stty 115200 -F /dev/ttyS0 && stty raw -echo -ctlecho" with netcat -f to connect to a serial port. @@ -27,13 +27,14 @@ config NETCAT_LISTEN default y depends on NETCAT help + usage: netcat [-t] [-lL COMMAND...] + -t allocate tty (must come before -l or -L) -l listen for one incoming connection. -L listen for multiple incoming connections (server mode). - Any additional command line arguments after -l or -L are executed - to handle each incoming connection. If none, the connection is - forwarded to stdin/stdout. + The command line after -l or -L is executed to handle each incoming + connection. If none, the connection is forwarded to stdin/stdout. For a quick-and-dirty server, try something like: netcat -s 127.0.0.1 -p 1234 -tL /bin/bash -l @@ -68,7 +69,7 @@ static void lookup_name(char *name, uint32_t *result) { struct hostent *hostbyname; - hostbyname = gethostbyname(name); + hostbyname = gethostbyname(name); // getaddrinfo if (!hostbyname) error_exit("no host '%s'", name); *result = *(uint32_t *)*hostbyname->h_addr_list; } @@ -102,8 +103,7 @@ void netcat_main(void) struct sockaddr_in address; // Setup socket - sockfd = socket(AF_INET, SOCK_STREAM, 0); - if (-1 == sockfd) perror_exit("socket"); + sockfd = xsocket(AF_INET, SOCK_STREAM, 0); fcntl(sockfd, F_SETFD, FD_CLOEXEC); temp = 1; setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, &temp, sizeof(temp)); @@ -140,7 +140,7 @@ void netcat_main(void) } // Do we need to return immediately because -l has arguments? - if ((toys.optflags&FLAG_l) && toys.optc) { + if ((toys.optflags & FLAG_l) && toys.optc) { if (fork()) goto cleanup; close(0); close(1); @@ -170,7 +170,7 @@ void netcat_main(void) if (!temp) close(sockfd); dup2(fd, 0); dup2(fd, 1); - dup2(fd, 2); + if (toys.optflags&FLAG_L) dup2(fd, 2); if (fd>2) close(fd); } } @@ -186,10 +186,8 @@ void netcat_main(void) // (Does not play well with -L, but what _should_ that do?) set_alarm(0); - if (CFG_NETCAT_LISTEN && (toys.optflags&(FLAG_L|FLAG_l) && toys.optc)) { - execvp(*toys.optargs, toys.optargs); - error_exit("Exec failed"); - } + if (CFG_NETCAT_LISTEN && (toys.optflags&(FLAG_L|FLAG_l) && toys.optc)) + xexec(toys.optargs); // Poll loop copying stdin->socket and socket->stdout. for (;;) { |