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dld-3_23.lha
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dld-3.2.3
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find_exec.c
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C/C++ Source or Header
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1991-05-30
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/* Given a filename, dld_find_executable searches the directories listed in the
environment variable PATH for a file with that filename.
A new copy of the complete path name of that file is returned. This new
string may be disposed by free() later on.
*/
/* This file is part of DLD, a dynamic link/unlink editor for C.
Copyright (C) 1990 by W. Wilson Ho.
The author can be reached electronically by how@cs.ucdavis.edu or
through physical mail at:
W. Wilson Ho
Division of Computer Science
University of California at Davis
Davis, CA 95616
*/
/* This program is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by the
Free Software Foundation; either version 1, or (at your option) any
later version. */
#include <sys/file.h>
#include <sys/param.h>
#include <strings.h>
#define DEFAULT_PATH ".:~/bin::/usr/local/bin:/usr/new:/usr/ucb:/usr/bin:/bin:/usr/hosts"
static char *
copy_of (s)
register char *s;
{
register char *p = (char *) malloc (strlen(s)+1);
if (!p) return 0;
*p = 0;
strcpy (p, s);
return p;
}
/* ABSOLUTE_FILENAME_P (fname): True if fname is an absolute filename */
#ifdef atarist
#define ABSOLUTE_FILENAME_P(fname) ((fname[0] == '/') || \
(fname[0] && (fname[1] == ':')))
#else
#define ABSOLUTE_FILENAME_P(fname) (fname[0] == '/')
#endif /* atarist */
char *
dld_find_executable (file)
char *file;
{
char *search;
register char *p;
if (ABSOLUTE_FILENAME_P(file))
return copy_of (file);
if (((search = (char *) getenv("DLDPATH")) == 0) &&
((search = (char *) getenv("PATH")) == 0))
search = DEFAULT_PATH;
p = search;
while (*p) {
char name[MAXPATHLEN];
register char *next;
next = name;
/* copy directory name into [name] */
while (*p && *p != ':') *next++ = *p++;
*next = 0;
if (*p) p++;
if (name[0] == '.' && name[1] == 0)
getwd (name);
strcat (name, "/");
strcat (name, file);
if (access (name, X_OK) == 0)
return copy_of (name);
}
return 0;
}