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CONTRIBUTIONS/cpm-handbook/cpmsrc/ERASE.C

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+#define VN "1.0 02/24/83"
+/* ERASE
+   This utility erases the specified file(s). It performs a logical
+   erasure by using a BDOS Delete function. */
+
+#include <LIBRARY.H>
+
+struct _fcb amb_fcb;		/* ambiguous name file control block */
+struct _fcb fcb;		/* used for BDOS Search Functions */
+
+char file_name[20];		/* formatted for display : d:FILENAME.TYP */
+short cur_disk;			/* current logical disk at start of program */
+				/* ERASE saves up the FCB's of the all the
+				   files that need to be erased in the
+				   following array. */
+#define MAXERA 1024
+struct _fcb era_fcb[MAXERA];
+int ecount;			/* count of number of files to be erased */
+int count;			/* used to access era_fcb during erasing */
+
+main(argc,argv)
+short argc;		/* argument count */
+char *argv[];		/* argument vector (pointer to an array of chars) */
+{
+
+printf("\nERASE Version %s (Library %s)",VN,LIBVN);
+chk_use(argc);			/* check usage */
+cur_disk = bdos(GETDISK);	/* get current default disk */
+
+ecount = 0;			/* initialize count of files to erase */
+
+setfcb(amb_fcb,argv[1]);	/* set ambiguous file name */
+if (amb_fcb.fcb_disk)		/* check if default disk to be used */
+	{
+	bdos(SETDISK,amb_fcb.fcb_disk + 1);	/* set to specified disk */
+	}
+
+	/* convert ambiguous file name for output */
+conv_fname(amb_fcb,file_name);
+printf("\n\nSearching for file(s) matching %s.",file_name);
+
+	/* set the file control block to indicate a "first" search */
+fcb.fcb_disk |= 0x80;	/* OR in the ms bit */
+
+	/* while not at the end of the directory, set the FCB
+	   to the next name that matches */
+while(get_nfn(amb_fcb,fcb))
+	{
+	conv_fname(fcb,file_name);
+		/* ask whether to erase file or not */
+	printf("\n\tErase %s y/n? ",file_name);
+	if (toupper(getchar()) == 'Y')
+		{
+		printf(" <== Will be Erased!");
+			/* add current fcb to array of fcb's */
+		movmem(fcb,&era_fcb[ecount++],FCBSIZE);
+			/* check that the table is not full */
+		if (ecount == MAXERA)
+			{
+			printf("\nWarning : Internal Table now full. No more files can be erased");
+			printf("\n   until those already specified have been erased.");
+			break;	/* break out of while loop */
+			}
+		}
+	}	/* all directory entries processed */
+
+if (ecount)
+	printf("\n\nErasing files now...");
+
+	/* now process each fcb in the array, erasing the files */
+for (count = 0;		/* starting with the first file in the array */
+     count < ecount;	/* until all active entries processed */
+     count++)		/* move to next fcb */
+	{
+	conv_fname(&era_fcb[count],file_name);	
+	if (bdos(DELETEF,&era_fcb[count]) == -1)	/* error? */
+		printf("\n\007Error trying to erase %s",file_name);
+	else	/* file erased */
+		printf("\n\tFile %s erased.",file_name);
+	}
+bdos(SETDISK,cur_disk);	/* reset to current disk */
+}
+
+
+chk_use(argc)		/* check usage */
+/* This function checks that the correct number of
+   parameters has been specified, outputting instructions
+   if not. */
+
+/* Entry Parameter */
+int argc;	/* Count of the number of arguments on the command line */
+{
+
+	/* The minimum value of argc is 1 (for the program name itself),
+	   so argc is always one greater than the number of parameters
+	   on the command line */
+
+if (argc != 2)
+	{
+	printf("\nUsage :");
+	printf("\n\tERASE {d:}file_name.typ");
+	exit();
+	}
+ 
+}
+
+