stdio/fputs.3

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  32 .\"     @(#)fputs.3     8.1 (Berkeley) 6/4/93
  33 .\" $FreeBSD: src/lib/libc/stdio/fputs.3,v 1.14 2007/04/19 14:01:04 phk Exp $
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  35 .Dd June 4, 1993
  36 .Dt FPUTS 3
  37 .Os
  38 .Sh NAME
  39 .Nm fputs ,
  40 .Nm puts
  41 .Nd output a line to a stream
  42 .Sh LIBRARY
  43 .Lb libc
  44 .Sh SYNOPSIS
  45 .In stdio.h
  46 .Ft int
  47 .Fo fputs
  48 .Fa "const char *restrict s"
  49 .Fa "FILE *restrict stream"
  50 .Fc
  51 .Ft int
  52 .Fo puts
  53 .Fa "const char *s"
  54 .Fc
  55 .Sh DESCRIPTION
  56 The function
  57 .Fn fputs
  58 writes the string pointed to by
  59 .Fa s
  60 to the stream pointed to by
  61 .Fa stream .
  62 .\" The terminating
  63 .\" .Dv NUL
  64 .\" character is not written.
  65 .Pp
  66 The function
  67 .Fn puts
  68 writes the string
  69 .Fa s ,
  70 and a terminating newline character,
  71 to the stream
  72 .Dv stdout .
  73 .Sh RETURN VALUES
  74 The functions
  75 .Fn fputs
  76 and
  77 .Fn puts
  78 return a nonnegative integer on success and
  79 .Dv EOF
  80 on error.
  81 .Sh ERRORS
  82 .Bl -tag -width Er
  83 .It Bq Er EBADF
  84 The
  85 .Fa stream
  86 argument
  87 is not a writable stream.
  88 .El
  89 .Pp
  90 The functions
  91 .Fn fputs
  92 and
  93 .Fn puts
  94 may also fail and set
  95 .Va errno
  96 for any of the errors specified for the routines
  97 .Xr write 2 .
  98 .Sh COMPATIBILITY
  99 .Fn fputs
 100 now returns a non-negative number (as opposed to 0)
 101 on successful completion.
 102 As a result, many tests (e.g., "fputs() == 0", "fputs() != 0")
 103 do not give the desired result.
 104 Use "fputs() != EOF" or "fputs() == EOF"
 105 to determine success or failure.
 106 .Sh SEE ALSO
 107 .Xr ferror 3 ,
 108 .Xr fputws 3 ,
 109 .Xr putc 3 ,
 110 .Xr stdio 3
 111 .Sh STANDARDS
 112 The functions
 113 .Fn fputs
 114 and
 115 .Fn puts
 116 conform to
 117 .St -isoC .
 118 While not mentioned in the standard, both
 119 .Fn fputs
 120 and
 121 .Fn puts
 122 print
 123 .Ql (null)
 124 if
 125 .Fa str
 126 is
 127 .Dv NULL .