taskset: add CPU affinity tool

Implements taskset(1) with hex mask and CPU list parsing/formatting, -p (pid
mode), -a (all-tasks), and exec mode. Includes stride notation in
format_cpu_list, comma-separated hex mask support from /proc/<pid>/status, and
unit + integration tests.

Author: jmr

Cargo.lock

@@ -46,6 +46,7 @@ feat_common_core = [
   "rev",
   "setpgid",
   "setsid",
+  "taskset",
   "uuidgen",
 ]
 
@@ -114,6 +115,7 @@ renice = { optional = true, version = "0.0.1", package = "uu_renice", path = "sr
 rev = { optional = true, version = "0.0.1", package = "uu_rev", path = "src/uu/rev" }
 setpgid = { optional = true, version = "0.0.1", package = "uu_setpgid", path = "src/uu/setpgid" }
 setsid = { optional = true, version = "0.0.1", package = "uu_setsid", path ="src/uu/setsid" }
+taskset = { optional = true, version = "0.0.1", package = "uu_taskset", path = "src/uu/taskset" }
 uuidgen = { optional = true, version = "0.0.1", package = "uu_uuidgen", path ="src/uu/uuidgen" }
 
 [dev-dependencies]

Cargo.toml

@@ -59,8 +59,9 @@ First, reimplement the most important tools from util-linux:
 - `kill`: Sends signals to processes.
 - `renice`: Alters process priority.
 - `prlimit`: Sets/gets process resource limits.
-- `taskset`: Sets/gets process CPU affinity.
 - `uclampset`: Manages process utilization clamping.
+  Done
+- `taskset`: Sets/gets process CPU affinity.
 
 ## User and Session Management
 - `su`: Changes user ID or becomes superuser.

README.md

@@ -0,0 +1,22 @@
+[package]
+name    = "uu_taskset"
+version = "0.0.1"
+edition = "2021"
+
+[lib]
+path = "src/taskset.rs"
+
+[[bin]]
+name = "taskset"
+path = "src/main.rs"
+
+[dependencies]
+clap      = { workspace = true }
+thiserror = { workspace = true }
+uucore    = { workspace = true }
+
+[target.'cfg(target_os = "linux")'.dependencies]
+nix = { workspace = true, features = ["sched"] }
+
+[dev-dependencies]
+tempfile = { workspace = true }

src/uu/taskset/Cargo.toml

@@ -0,0 +1 @@
+uucore::bin!(uu_taskset);