C Language Beginner Drawing practice

Task One, Echo

Program Source code:

#include<stdio.h> #include<stdlib.h> #include<string.h> intMainintargcChar*argv[]) { int Nflag; if (*++ARGV &&!strcmp (*ARGV, "-n")) { ++ARGV; Nflag = 1; } Else Nflag = 0; while (*ARGV) { printf ("%s", *ARGV); if (*++ARGV) Putchar ("); } if (!nflag) Putchar (' \ n '); Exit (0); }

Task Requirements:
This program is the source code for the Echo implementation of commands under UNIX (with appropriate deletions and adornments).
Please use the structured flowchart to draw the procedure in the main function of this program .

task Two, Sleep

Program Source code:

#include<sys/time.h> #include<time.h> #include<ctype.h> #include<math.h> #include<signal.h> #include<stdio.h> #include<stdlib.h> #include<unistd.h> #include<locale.h> voidUsage () { (void) fprintf (stderr, "Usage:sleep seconds\n"); Exit (1); } voidAlarmhandle () { _exit (0); } intMainintargcChar *Argv[]) { Char *arg, *temp; Double Val, ival, fval; struct timespec ntime; int Fracflag; int ch; SetLocale (Lc_all, ""); (void) signal (SIGALRM, alarmhandle); while (ch = getopt (argc, argv, ""))!! =-1) Switch (CH) { Case ‘?‘: default: Usage (); } ARGC-= Optind; argv + = Optind; if (argc! = 1) usage (); Fracflag = 0; arg = *ARGV; for (temp = arg; *temp! = '); temp++) if (!isdigit (*temp)) fracflag++; if (Fracflag) { val = atof (ARG); if (Val <= 0) exit (0); Ival = Floor (val); fval = (1000000000 * (Val-ival)); Ntime.tv_sec = ival; Ntime.tv_nsec = fval; } Else { Ntime.tv_sec = Atol (ARG); if (ntime.tv_sec <= 0) Exit (0); ntime.tv_nsec = 0; } (void) Nanosleep (&ntime, NULL); Exit (0); }

Requirements:
This program is the source code for the sleep implementation of commands under UNIX (with appropriate deletions and adornments).
Please use the structured flowchart to draw the procedure in the main function of this program.

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C Language Beginner Drawing practice