Index: lib/libc/gen/getprogname.3 =================================================================== --- lib/libc/gen/getprogname.3 +++ lib/libc/gen/getprogname.3 @@ -31,7 +31,7 @@ .\" .\" $FreeBSD$ .\" -.Dd May 1, 2001 +.Dd April 17, 2021 .Dt GETPROGNAME 3 .Os .Sh NAME @@ -84,6 +84,32 @@ .Fn setprogname allows the aforementioned library to learn the program name without modifications to the start-up code. +.Sh EXAMPLES +The following example presents a simple program, which shows the difference +between +.Fn getprogname +and +.Va "argv[0]" . +.Bd -literal -offset indent +#include +#include + +int +main(int argc, char** argv) +{ + printf("getprogname(): %s\en", getprogname()); + printf("argv[0]: %s\en", argv[0]); + return (0); +} +.Ed +.Pp +When compiled and executed (e.g., with +.Ql ./a.out ) +the output of the program is going to look like this: +.Bd -literal -offset indent +getprogname(): a.out +argv[0]: ./a.out +.Ed .Sh SEE ALSO .Xr err 3 , .Xr setproctitle 3