jchvr@ihlpg.UUCP (VanRietschote) (01/07/86)
----
PUREPATH when used will take out double entries from the $PATH shell
variable. This will speed up the searching for a command and will keep
$PATH within lenth limits (which is needed by some programs like post(1)
which assume that $PATH is shorten then 512 256 or something like that.
For describtion see next item with manual page.
You are free to use or abuse this program at your own risk.
#--- cut here ----
/* purepath.c: -*-update-version-*-
** to make PATH contain every entry only once
** HFVR VERSION=Fri Oct 11 13:57:26 1985
*/
#include <stdio.h>
char NAME[] = "purepath";
char *PATH;
typedef enum{FALSE,TRUE} BOOL;
typedef struct part
{ char *string;
struct part *next;
} PART;
PART *root = NULL;
/*newpart: to create and init new part of path record */
PART *newpart()
{ extern PART *malloc();
PART *ptr;
static char EMPTY[] = "";
ptr = malloc(sizeof(PART));
if (ptr == NULL) {
fprintf(stderr,"\007%s: Out of memory. Aborting.\n",NAME);
exit(1);
}
ptr->string = EMPTY;
ptr->next = NULL;
return(ptr);
}/*newpart*/
void init()
{ char *charptr;
PART *ptr;
charptr = PATH;
while (charptr[0] != '\0') {
ptr = root;
root = newpart();
root->next = ptr;
root->string = charptr;
/* skip till ':' or EOS, then replace ':' by EOS */
while ( (charptr[0] != ':') && (charptr[0] != '\0') ) charptr++;
if (charptr[0] != '\0') {
charptr[0] = '\0';
charptr++;
}
}/*while*/
}/*init*/
/* return TRUE if string pointed to is unique */
BOOL unique(ptr)
PART *ptr;
{ BOOL found;
PART *ptr1;
if (ptr == NULL) return(TRUE);
found = FALSE;
ptr1 = ptr->next;
while ( (!found) && (ptr1 != NULL) ){
if (strcmp(ptr->string,ptr1->string) == 0) {
found = TRUE;
} else {
found = FALSE;
}
ptr1 = ptr1->next;
}/*while*/
if (found) return(FALSE);
return(TRUE);
}/*unique*/
/* print string in PART, first one first */
void printpart(ptr)
PART *ptr;
{
if (ptr == NULL) return;
printpart(ptr->next);
if (unique(ptr)) {
printf("%s:",ptr->string);
}
}/*printpart*/
/* print all parts from root down */
void finit()
{
printpart(root);
}/*finit*/
void usage()
{
fprintf(stderr,"Usage: %s [-V] [-H] [path]\n",NAME);
fprintf(stderr,"Where -V displays version\n");
fprintf(stderr," -H displays this message\n");
}/*usage*/
/* parse each - option */
void parse(ch)
{
switch (ch) {
case 'v' :
case 'V' : printf("%s: version 0.99\n",NAME);
exit(1);
break;
case 'H' : usage();
exit(1);
break;
default : fprintf(stderr,"\007%s: illegal option -%c\n",NAME,ch);
usage();
exit(1);
break;
}/*switch*/
}/*parse*/
/* parse and act on all argv */
void parseoptions(argc,argv)
int argc;
char *argv[];
{ extern char *getenv();
int i;
PATH = getenv("PATH"); /* default */
for ( i = 1 ; i < argc ; i++) {
switch(argv[i][0]) {
case '-' : parse(argv[i][1]);
break;
default : PATH = argv[i];
break;
}
}/*for*/
}/*parseoptions*/
main(argc,argv)
int argc;
char *argv[];
{
parseoptions(argc,argv);
init();
finit();
}/*main*/