execv

execv is a POSIX-compatible function in the exec family that replaces the current process image with a new executable. If successful, the running process becomes the new program, and the process ID remains unchanged; all prior code, data, and stack are replaced. The call does not return to the original program when the new program starts.

Signature and parameters: int execv(const char *path, char *const argv[]); path specifies the executable file to run, which may be absolute or relative. argv is a null-terminated array of argument strings passed to the new program, with argv[0] traditionally containing the program name.

Environment and behavior: execv uses the environment of the calling process; it does not take an environment pointer. To specify a custom environment, use the related function execve, which accepts a third parameter envp. If the call succeeds, control never returns to the caller; on failure, it returns -1 and sets errno.

Path resolution and errors: execv does not search the PATH; the path must directly reference an executable file. The kernel performs permission checks and loads the program into memory. Typical errno codes on failure include ENOENT (no such file or directory) and EACCES (permission denied).

Related variants: The exec family includes execl, execle, execlp, execv, execve, and execvp. Variants with a 'p' search the PATH, while those with 'e' allow supplying a custom environment; variants with 'l' pass a list of arguments and those with 'v' use an argv vector.