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/* Copyright (c) 1988 Regents of the University of California */ |
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|
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#ifndef lint |
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static char SCCSid[] = "$SunId$ LBL"; |
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#endif |
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|
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/* |
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* devcomm.c - communication routines for separate drivers. |
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* |
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* 10/5/88 |
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*/ |
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|
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#include <stdio.h> |
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|
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#include <signal.h> |
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|
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#include "color.h" |
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|
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#include "driver.h" |
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|
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#ifndef DEVPATH |
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#define DEVPATH getenv("PATH") /* device search path */ |
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#endif |
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|
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#ifndef BSD |
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#define vfork fork |
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#endif |
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|
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#ifndef WFLUSH |
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#define WFLUSH 30 /* flush after this many rays */ |
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#endif |
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|
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extern char *getpath(), *getenv(); |
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|
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int onsigio(); |
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|
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int comm_close(), comm_clear(), comm_paintr(), comm_errout(), |
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comm_getcur(), comm_comout(), comm_comin(); |
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|
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struct driver comm_driver, comm_default = { |
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comm_close, comm_clear, comm_paintr, comm_getcur, |
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comm_comout, comm_comin, |
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MAXRES, MAXRES, 0 |
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}; |
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|
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FILE *devin, *devout; |
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|
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int devchild; |
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|
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|
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struct driver * |
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comm_init(argv) /* set up and execute driver */ |
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char *argv[]; |
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{ |
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char *devname; |
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int p1[2], p2[2]; |
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|
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if ((devname = getpath(argv[0], DEVPATH)) == NULL) { |
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stderr_v(argv[0]); |
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stderr_v(": not found\n"); |
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return(NULL); |
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} |
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if (pipe(p1) == -1 || pipe(p2) == -1) |
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goto syserr; |
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if ((devchild = vfork()) == 0) { |
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close(p1[1]); |
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close(p2[0]); |
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if (p1[0] != 0) { |
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dup2(p1[0], 0); |
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close(p1[0]); |
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} |
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if (p2[1] != 1) { |
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dup2(p2[1], 1); |
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close(p2[1]); |
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} |
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execv(devname, argv); |
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stderr_v(devname); |
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stderr_v(": cannot execute\n"); |
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_exit(127); |
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} |
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if (devchild == -1) |
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goto syserr; |
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close(p1[0]); |
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close(p2[1]); |
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if ((devout = fdopen(p1[1], "w")) == NULL) |
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goto syserr; |
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if ((devin = fdopen(p2[0], "r")) == NULL) |
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goto syserr; |
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bcopy(&comm_default, &comm_driver, sizeof(comm_driver)); |
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signal(SIGIO, onsigio); |
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errvec = comm_errout; /* set error vector */ |
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cmdvec = comm_comout; |
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if (wrnvec != NULL) |
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wrnvec = comm_comout; |
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return(&comm_driver); |
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syserr: |
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perror(argv[0]); |
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return(NULL); |
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} |
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|
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|
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static |
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comm_close() /* done with driver */ |
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{ |
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int pid; |
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|
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errvec = stderr_v; /* reset error vector */ |
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cmdvec = NULL; |
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if (wrnvec != NULL) |
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wrnvec = stderr_v; |
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signal(SIGIO, SIG_DFL); |
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fclose(devout); |
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fclose(devin); |
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while ((pid = wait(0)) != -1 && pid != devchild) |
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; |
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} |
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|
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|
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static |
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comm_clear(xres, yres) /* clear screen */ |
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int xres, yres; |
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{ |
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putc(COM_CLEAR, devout); |
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fwrite(&xres, sizeof(xres), 1, devout); |
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fwrite(&yres, sizeof(yres), 1, devout); |
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fflush(devout); |
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} |
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|
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|
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static |
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comm_paintr(col, xmin, ymin, xmax, ymax) /* paint a rectangle */ |
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COLOR col; |
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int xmin, ymin, xmax, ymax; |
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{ |
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extern long nrays; /* number of rays traced */ |
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static long lastflush = 0; /* ray count at last flush */ |
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|
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putc(COM_PAINTR, devout); |
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fwrite(col, sizeof(COLOR), 1, devout); |
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fwrite(&xmin, sizeof(xmin), 1, devout); |
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fwrite(&ymin, sizeof(ymin), 1, devout); |
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fwrite(&xmax, sizeof(xmax), 1, devout); |
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fwrite(&ymax, sizeof(ymax), 1, devout); |
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if (nrays - lastflush >= WFLUSH) { |
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fflush(devout); |
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lastflush = nrays; |
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} |
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} |
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|
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|
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static int |
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comm_getcur(xp, yp) /* get and return cursor position */ |
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int *xp, *yp; |
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{ |
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int c; |
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|
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putc(COM_GETCUR, devout); |
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fflush(devout); |
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if (getc(devin) != COM_GETCUR) |
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reply_error("getcur"); |
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c = getc(devin); |
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fread(xp, sizeof(*xp), 1, devin); |
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fread(yp, sizeof(*yp), 1, devin); |
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return(c); |
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} |
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|
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|
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static |
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comm_comout(str) /* print string to command line */ |
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char *str; |
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{ |
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putc(COM_COMOUT, devout); |
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myputs(str, devout); |
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fflush(devout); |
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} |
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|
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|
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static |
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comm_comin(buf) /* read string from command line */ |
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char *buf; |
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{ |
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putc(COM_COMIN, devout); |
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fflush(devout); |
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if (getc(devin) != COM_COMIN) |
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reply_error("comin"); |
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mygets(buf, devin); |
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comm_driver.inpready = 0; |
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} |
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|
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|
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static |
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comm_errout(str) /* display an error message */ |
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char *str; |
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{ |
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comm_comout(str); |
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stderr_v(str); /* send to standard error also */ |
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} |
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|
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|
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static |
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mygets(s, fp) /* get string from file (with nul) */ |
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register char *s; |
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register FILE *fp; |
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{ |
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register int c; |
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|
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while ((c = getc(fp)) != EOF) |
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if ((*s++ = c) == '\0') |
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return; |
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*s = '\0'; |
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} |
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|
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|
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static |
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myputs(s, fp) /* put string to file (with nul) */ |
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register char *s; |
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register FILE *fp; |
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{ |
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do |
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putc(*s, fp); |
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while (*s++); |
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} |
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|
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|
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static |
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reply_error(routine) /* what should we do here? */ |
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char *routine; |
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{ |
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stderr_v(routine); |
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stderr_v(": driver reply error\n"); |
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quit(1); |
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} |
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|
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|
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static |
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onsigio() /* input ready */ |
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{ |
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comm_driver.inpready++; |
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} |