*
* Licensed under GPLv2 or later, see file LICENSE in this source tree.
*/
+//config:config WATCH
+//config: bool "watch (4.1 kb)"
+//config: default y
+//config: help
+//config: watch is used to execute a program periodically, showing
+//config: output to the screen.
+
+//applet:IF_WATCH(APPLET(watch, BB_DIR_BIN, BB_SUID_DROP))
+
+//kbuild:lib-$(CONFIG_WATCH) += watch.o
+
+//usage:#define watch_trivial_usage
+//usage: "[-n SEC] [-t] PROG ARGS"
+//usage:#define watch_full_usage "\n\n"
+//usage: "Run PROG periodically\n"
+//usage: "\n -n Loop period in seconds (default 2)"
+//usage: "\n -t Don't print header"
+//usage:
+//usage:#define watch_example_usage
+//usage: "$ watch date\n"
+//usage: "Mon Dec 17 10:31:40 GMT 2000\n"
+//usage: "Mon Dec 17 10:31:42 GMT 2000\n"
+//usage: "Mon Dec 17 10:31:44 GMT 2000"
/* BB_AUDIT SUSv3 N/A */
/* BB_AUDIT GNU defects -- only option -n is supported. */
#include "libbb.h"
+#define ESC "\033"
+
// procps 2.0.18:
// watch [-d] [-n seconds]
// [--differences[=cumulative]] [--interval=seconds] command
xopen("/dev/null", O_RDONLY);
#endif
- opt_complementary = "-1:n+"; // at least one param; -n NUM
- // "+": stop at first non-option (procps 3.x only)
- opt = getopt32(argv, "+dtn:", &period);
+ // "+": stop at first non-option (procps 3.x only); -n NUM
+ // at least one param
+ opt = getopt32(argv, "^+" "dtn:+" "\0" "-1", &period);
argv += optind;
// watch from both procps 2.x and 3.x does concatenation. Example:
header = NULL;
while (1) {
/* home; clear to the end of screen */
- printf("\033[H""\033[J");
+ printf(ESC"[H" ESC"[J");
if (!(opt & 0x2)) { // no -t
const unsigned time_len = sizeof("1234-67-90 23:56:89");
- time_t t;
// STDERR_FILENO is procps3 compat:
// "watch ls 2>/dev/null" does not detect tty size
- get_terminal_width_height(STDERR_FILENO, &new_width, NULL);
+ new_width = get_terminal_width(STDERR_FILENO);
if (new_width != width) {
width = new_width;
free(header);
header = xasprintf("Every %us: %-*s", period, (int)width, cmd);
}
- time(&t);
- if (time_len < width)
- strftime(header + width - time_len, time_len,
- "%Y-%m-%d %H:%M:%S", localtime(&t));
+ if (time_len < width) {
+ strftime_YYYYMMDDHHMMSS(
+ header + width - time_len,
+ time_len,
+ /*time_t*:*/ NULL
+ );
+ }
// compat: empty line between header and cmd output
printf("%s\n\n", header);