ref: a8d00e5d56b261376410c3c87c46327362763bd8
dir: /sys/src/cmd/date.c/
#include <u.h> #include <libc.h> int uflg, nflg, iflg, tflg; char* isodate(Tm *t) { static char c[25]; /* leave room to append isotime */ snprint(c, 11, "%04d-%02d-%02d", t->year + 1900, t->mon + 1, t->mday); return c; } char* isotime(Tm *t) { int tz; char *c, *d; d = isodate(t); c = d+10; snprint(c, 10, "T%02d:%02d:%02d", t->hour, t->min, t->sec); /* append to isodate */ tz = t->tzoff / 60; if(t->tzoff) { /* localtime */ if (t->tzoff > 0) { c[9] = '+'; } else { c[9] = '-'; tz = -tz; } snprint(c+10, 5, "%02d%02d", tz / 60, tz % 60); } else { c[9] = 'Z'; c[10] = 0; } return d; } void main(int argc, char *argv[]) { ulong now; Tm *tm; ARGBEGIN{ case 'n': nflg = 1; break; case 'u': uflg = 1; break; case 't': tflg = 1; /* implies -i */ case 'i': iflg = 1; break; default: fprint(2, "usage: date [-itun] [seconds]\n"); exits("usage"); }ARGEND if(argc == 1) now = strtoul(*argv, 0, 0); else now = time(0); if(nflg) print("%ld\n", now); else { tm = uflg ? gmtime(now) : localtime(now); if(iflg) { if(tflg) print("%s\n", isotime(tm)); else print("%s\n", isodate(tm)); } else print("%s", asctime(tm)); } exits(0); }