| bzero.3 (d1d015864103b253b3fcb2f72a0da5b0cfeb31b6) | bzero.3 (78b59024b537e0993c0272fe57b8d23da5eaf0ce) |
|---|---|
| 1.\" Copyright (c) 1990, 1991, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" This code is derived from software contributed to Berkeley by 5.\" Chris Torek. 6.\" 7.\" Redistribution and use in source and binary forms, with or without 8.\" modification, are permitted provided that the following conditions --- 21 unchanged lines hidden (view full) --- 30.\" 31.\" @(#)bzero.3 8.1 (Berkeley) 6/4/93 32.\" $FreeBSD$ 33.\" 34.Dd June 4, 1993 35.Dt BZERO 3 36.Os 37.Sh NAME | 1.\" Copyright (c) 1990, 1991, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" This code is derived from software contributed to Berkeley by 5.\" Chris Torek. 6.\" 7.\" Redistribution and use in source and binary forms, with or without 8.\" modification, are permitted provided that the following conditions --- 21 unchanged lines hidden (view full) --- 30.\" 31.\" @(#)bzero.3 8.1 (Berkeley) 6/4/93 32.\" $FreeBSD$ 33.\" 34.Dd June 4, 1993 35.Dt BZERO 3 36.Os 37.Sh NAME |
| 38.Nm bzero | 38.Nm bzero , 39.Nm explicit_bzero |
| 39.Nd write zeroes to a byte string 40.Sh LIBRARY 41.Lb libc 42.Sh SYNOPSIS 43.In strings.h 44.Ft void 45.Fn bzero "void *b" "size_t len" | 40.Nd write zeroes to a byte string 41.Sh LIBRARY 42.Lb libc 43.Sh SYNOPSIS 44.In strings.h 45.Ft void 46.Fn bzero "void *b" "size_t len" |
| 47.Ft void 48.Fn explicit_bzero "void *b" "size_t len" |
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| 46.Sh DESCRIPTION 47The 48.Fn bzero 49function 50writes 51.Fa len 52zero bytes to the string 53.Fa b . 54If 55.Fa len 56is zero, 57.Fn bzero 58does nothing. | 49.Sh DESCRIPTION 50The 51.Fn bzero 52function 53writes 54.Fa len 55zero bytes to the string 56.Fa b . 57If 58.Fa len 59is zero, 60.Fn bzero 61does nothing. |
| 62.Pp 63The 64.Fn explicit_bzero 65variant behaves the same, but will not be removed by a compiler's dead store 66optimization pass, making it useful for clearing sensitive memory such as a 67password. |
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| 59.Sh SEE ALSO 60.Xr memset 3 , 61.Xr swab 3 62.Sh HISTORY 63A 64.Fn bzero 65function 66appeared in 67.Bx 4.3 . 68Its prototype existed previously in 69.In string.h 70before it was moved to 71.In strings.h 72for 73.St -p1003.1-2001 74compliance. | 68.Sh SEE ALSO 69.Xr memset 3 , 70.Xr swab 3 71.Sh HISTORY 72A 73.Fn bzero 74function 75appeared in 76.Bx 4.3 . 77Its prototype existed previously in 78.In string.h 79before it was moved to 80.In strings.h 81for 82.St -p1003.1-2001 83compliance. |
| 84.Pp 85The 86.Fn explicit_bzero 87function first appeared in 88.Ox 5.5 89and 90.Fx 11.0 . |
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