os.Exec pitfalls

`exec.Cmd` cannot be reused

An exec.Cmd cannot be reused after calling its Run, Output or CombinedOutput methods.

cmd := exec.Command("go", "version")
_, err := cmd.CombinedOutput()
if err != nil {
	log.Fatalf("first cmd.CombintedOutput() failed with '%s'\n", err)
}

_, err = cmd.CombinedOutput()
if err != nil {
	log.Fatalf("second cmd.CombintedOutput() failed with '%s'\n", err)
}

try online

2020/07/12 07:36:21 second cmd.CombintedOutput() failed with 'exec: Stdout already set'
exit status 1

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Executing commands:

*Basic command execution

*More advanced command execution

*Timing out process execution

*os.Exec pitfalls

Table Of Contents

16Methods

18Defer

21Channels and select

22Mutex

23Packages

24Files and I/O

25Time and date

26Command line arguments

27Logging

28Executing commands

29Hex, base64 encoding

30JSON

31XML

32CSV

33YAML

34SQL

35HTTP Client

36HTTP Server

37Text and HTML templates

38Reflection

39Context

40Package fmt

41OS Signals

42Testing

43Calling C from GO with cgo

44Profiling using go tool pprof

45Cross compilation

46Conditional compilation with build tags

47Inlining functions

48sync.Pool for better performance

49gob

50Plugin

51HTTP server middleware

52Protobuf in Go

53Console I/O

54Cryptography

55Images (PNG, JPEG, BMP, TIFF, WEBP, VP8, GIF)

56The Go Command

57Testing code with CI services

58Windows GUI programming

59Contributors

os.Exec pitfalls

exec.Cmd cannot be reused

`exec.Cmd` cannot be reused