gen/FreeBSD/getprogname.3

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   2 .\" Copyright (c) 2001 Christopher G. Demetriou
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  32 .\" $FreeBSD: src/lib/libc/gen/getprogname.3,v 1.5 2001/10/01 16:08:51 ru Exp $
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  34 .Dd May 1, 2001
  35 .Dt GETPROGNAME 3
  36 .Os
  37 .Sh NAME
  38 .Nm getprogname ,
  39 .Nm setprogname
  40 .Nd get or set the program name
  41 .Sh LIBRARY
  42 .Lb libc
  43 .Sh SYNOPSIS
  44 .In stdlib.h
  45 .Ft const char *
  46 .Fn getprogname "void"
  47 .Ft void
  48 .Fn setprogname "const char *progname"
  49 .Sh DESCRIPTION
  50 The
  51 .Fn getprogname
  52 and
  53 .Fn setprogname
  54 functions manipulate the name of the current program.
  55 They are used by error-reporting routines to produce
  56 consistent output.
  57 .Pp
  58 The
  59 .Fn getprogname
  60 function returns the name of the program.
  61 If the name has not been set yet, it will return
  62 .Dv NULL .
  63 .Pp
  64 The
  65 .Fn setprogname
  66 function sets the name of the program to be the last component of the
  67 .Fa progname
  68 argument.
  69 Since a pointer to the given string is kept as the program name,
  70 it should not be modified for the rest of the program's lifetime.
  71 .Pp
  72 In
  73 .Fx ,
  74 the name of the program is set by the start-up code that is run before
  75 .Fn main ;
  76 thus,
  77 running
  78 .Fn setprogname
  79 is not necessary.
  80 Programs that desire maximum portability should still call it;
  81 on another operating system,
  82 these functions may be implemented in a portability library.
  83 Calling
  84 .Fn setprogname
  85 allows the aforementioned library to learn the program name without
  86 modifications to the start-up code.
  87 .Sh SEE ALSO
  88 .Xr err 3
  89 .Sh HISTORY
  90 These functions first appeared in
  91 .Nx 1.6 ,
  92 and made their way into
  93 .Fx 4.4 .