1 // Copyright 2018 The Prometheus Authors 2 // Licensed under the Apache License, Version 2.0 (the "License"); 3 // you may not use this file except in compliance with the License. 4 // You may obtain a copy of the License at 5 // 6 // http://www.apache.org/licenses/LICENSE-2.0 7 // 8 // Unless required by applicable law or agreed to in writing, software 9 // distributed under the License is distributed on an "AS IS" BASIS, 10 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 11 // See the License for the specific language governing permissions and 12 // limitations under the License. 13 14 package procfs 15 16 import ( 17 "fmt" 18 19 "github.com/prometheus/procfs/internal/util" 20 ) 21 22 // ProcIO models the content of /proc/<pid>/io. 23 type ProcIO struct { 24 // Chars read. 25 RChar uint64 26 // Chars written. 27 WChar uint64 28 // Read syscalls. 29 SyscR uint64 30 // Write syscalls. 31 SyscW uint64 32 // Bytes read. 33 ReadBytes uint64 34 // Bytes written. 35 WriteBytes uint64 36 // Bytes written, but taking into account truncation. See 37 // Documentation/filesystems/proc.txt in the kernel sources for 38 // detailed explanation. 39 CancelledWriteBytes int64 40 } 41 42 // IO creates a new ProcIO instance from a given Proc instance. 43 func (p Proc) IO() (ProcIO, error) { 44 pio := ProcIO{} 45 46 data, err := util.ReadFileNoStat(p.path("io")) 47 if err != nil { 48 return pio, err 49 } 50 51 ioFormat := "rchar: %d\nwchar: %d\nsyscr: %d\nsyscw: %d\n" + 52 "read_bytes: %d\nwrite_bytes: %d\n" + 53 "cancelled_write_bytes: %d\n" 54 55 _, err = fmt.Sscanf(string(data), ioFormat, &pio.RChar, &pio.WChar, &pio.SyscR, 56 &pio.SyscW, &pio.ReadBytes, &pio.WriteBytes, &pio.CancelledWriteBytes) 57 58 return pio, err 59 } 60