Hi all,
An empty PATH element (":xxx" or "xxx::xxx" or "xxx:") is to be considered as
the current directory (from the very first days of Unix).
However, Cygwin does not seem to obey the rule.
Consider the following simple C program:
$ cat hello.c
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
int main(int argc, const char* argv[])
{
if (argc < 2) {
const char* prog = strrchr(argv[0], '/');
if (!prog++)
prog = argv[0];
execlp(prog, prog, "Hello", NULL); // execute just by the program name
perror("exec");
return 1;
}
printf("%s\n", argv[1]);
return 0;
}
Now compare the execution on Linux and Cygwin:
Linux:
$ gcc -Wall -o hello hello.c
$ hello
bash: hello: command not found
$ ./hello
exec: No such file or directory
$ PATH=".:$PATH" ./hello
Hello
$ PATH=":$PATH" ./hello
Hello
$ PATH="${PATH}:" ./hello
Hello
Cygwin:
$ gcc -Wall -o hello hello.c
$ hello
-bash: hello: command not found
$ ./hello
exec: No such file or directory
$ PATH=".:$PATH" ./hello
Hello
$ PATH=":$PATH" ./hello
exec: No such file or directory
$ PATH="${PATH}:" ./hello
exec: No such file or directory
As you can see, the execution failed when an empty PATH element was added on
Cygwin
(yet it was perfectly fine on Linux).
Anton Lavrentiev
Contractor NIH/NLM/NCBI
--
Problem reports: https://cygwin.com/problems.html
FAQ: https://cygwin.com/faq/
Documentation: https://cygwin.com/docs.html
Unsubscribe info: https://cygwin.com/ml/#unsubscribe-simple
