The program invoked inherits the calling process's PID, and any open file descriptors that are not set to close on exec. Signals pending on the parent process are cleared.
Any signals set to be caught by the calling process are reset to their default behaviour.
The file or a script interpreter is not a regular file. The file system is mounted noexec . The file system is mounted nosuid , the user is not the superuser, and the file has an SUID or SGID bit set. The process is being traced, the user is not the superuser and the file has an SUID or SGID bit set. The argument list is too big.