/* uudecode.c - convert ascii-encoded files back to their original form * Usage: uudecode [infile] * * This command differs from the regular UNIX one in that the embedded * file name "/dev/stdout" is recognized, allowing it to be used in a pipeline * * Written and placed in the public domain by Phil Karn, KA9Q 31 March 1987 */#include <stdio.h>#define	LINELEN	80main(argc,argv)int argc;char *argv[];{	char linebuf[LINELEN],*index(),*fgets();	register char *cp;	int linelen,i;	FILE *in,*out;		if(argc > 1){		if((in = fopen(argv[1],"r")) == NULL){			fprintf(stderr,"Can't read %s\n",argv[1]);			exit(1);		}	} else		in = stdin;	/* Find begin line */	while(fgets(linebuf,LINELEN,in) != NULL){		if((cp = index(linebuf,'\n')) != NULL)			*cp = '\0';		if(strncmp(linebuf,"begin",5) == 0)			break;	}	if(feof(in)){		fprintf(stderr,"No begin found\n");		exit(1);	}	/* Find beginning of file name */	cp = &linebuf[6];	if((cp = index(cp,' ')) != NULL)		cp++;	/* Set up output stream */	if(cp == NULL || strcmp(cp,"/dev/stdout") == 0){		out = stdout;	} else if((out = fopen(cp,"w")) == NULL){			fprintf(stderr,"Can't open %s\n",cp);			exit(1);	}	/* Now crunch the input file */	while(fgets(linebuf,LINELEN,in) != NULL){		linelen = linebuf[0] - ' ';		if(linelen == 0 || strncmp(linebuf,"end",3) == 0)			break;		for(cp = &linebuf[1];linelen > 0;cp += 4){			for(i=0;i<4;i++)				cp[i] -= ' ';			putc((cp[0] << 2) | ((cp[1] >> 4) & 0x3),out);			if(--linelen > 0)				putc((cp[1] << 4) | ((cp[2] >> 2) & 0xf),out);			if(--linelen > 0)				putc((cp[2] << 6) | cp[3],out);			linelen--;		}	}	fclose(out);}