#pragma prototyped
static const char usage[] =
"[-?\n@(#)$Id: dirname (AT&T Research) 2000-03-07 $\n]"
USAGE_LICENSE
"[+NAME?dirname - return directory portion of file name]"
"[+DESCRIPTION?\bdirname\b treats \astring\a as a file name and returns "
"the name of the directory containing the file name by deleting "
"the last component from \astring\a.]"
"[+?If \astring\a consists solely of \b/\b characters the output will "
"be a single \b/\b unless \bPATH_LEADING_SLASHES\b returned by "
"\bgetconf\b(1) is \b1\b and \astring\a consists of multiple "
"\b/\b characters in which case \b//\b will be output. "
"Otherwise, trailing \b/\b characters are removed, and if "
"there are no remaining \b/\b characters in \astring\a, "
"the string \b.\b will be written to standard output. "
"Otherwise, all characters following the last \b/\b are removed. "
"If the remaining string consists solely of \b/\b characters, "
"the output will be as if the original string had consisted solely "
"as \b/\b characters as described above. Otherwise, all "
"trailing slashes are removed and the output will be this string "
"unless this string is empty. If empty the output will be \b.\b.]"
"\n"
"\n string\n"
"\n"
"[+EXIT STATUS?]{"
"[+0?Successful Completion.]"
"[+>0?An error occurred.]"
"}"
"[+SEE ALSO?\bbasename\b(1), \bgetconf\b(1), \bdirname\b(3)]"
;
#include <cmd.h>
static void l_dirname(register Sfio_t *outfile, register const char *pathname)
{
register const char *last;
for(last=pathname; *last; last++);
while(last>pathname && *--last=='/');
for(;last>pathname && *last!='/';last--);
if(last==pathname)
{
if(*pathname!='/')
last = pathname = ".";
}
else
{
for(;*last=='/' && last > pathname; last--);
}
if(last!=pathname && pathname[0]=='/' && pathname[1]=='/')
{
while(pathname[2]=='/' && pathname<last)
pathname++;
if(last!=pathname && pathname[0]=='/' && pathname[1]=='/' && *astconf("PATH_LEADING_SLASHES",NiL,NiL)!='1')
pathname++;
}
sfwrite(outfile,pathname,last+1-pathname);
sfputc(outfile,'\n');
}
int
b_dirname(int argc,register char *argv[], void* context)
{
register int n;
cmdinit(argc, argv, context, ERROR_CATALOG, 0);
while (n = optget(argv, usage)) switch (n)
{
case ':':
error(2, "%s", opt_info.arg);
break;
case '?':
error(ERROR_usage(2), "%s", opt_info.arg);
break;
}
argv += opt_info.index;
argc -= opt_info.index;
if(error_info.errors || argc != 1)
error(ERROR_usage(2),"%s", optusage(NiL));
l_dirname(sfstdout,argv[0]);
return(0);
}