1.\" $NetBSD: qsubst.1,v 1.6 2017/02/22 14:01:40 abhinav Exp $ 2.\" 3.\" This file is in the public domain. 4.Dd September 4, 1999 5.Dt QSUBST 1 6.Os 7.Sh NAME 8.Nm qsubst 9.Nd query-replace strings in files 10.Sh SYNOPSIS 11.Nm 12.Ar str1 13.Ar str2 14.Op Ar flags 15.Ar file 16.Op Ar file Op Ar ... 17.Sh DESCRIPTION 18.Nm 19reads its options (see below) to get a list of files. 20For each file on this list, it then replaces 21.Ar str1 22with 23.Ar str2 24wherever possible in that file, depending on user input (see below). 25The result is written back onto the original file. 26.Pp 27For each potential substitution found, the user is prompted with a few 28lines before and after the line containing the string to be 29substituted. 30The string itself is displayed using the terminal's standout mode, if any. 31Then one character is read from the terminal. 32This is then interpreted as follows (this is designed to be like Emacs' 33query-replace-string): 34.Bl -tag -width "space" -compact -offset indent 35.It space 36Replace this occurrence and go on to the next one. 37.It \&. 38Replace this occurrence and don't change any more in this file (i.e., go 39on to the next file). 40.It \&, 41Tentatively replace this occurrence. 42The lines as they would look if the substitution were made are printed out. 43Then another character is read and it is used to decide the result as if 44the tentative replacement had not happened. 45.It n 46Don't change this one; just go on to the next one. 47.It \&^G 48Don't change this one or any others in this file, but instead simply go 49on to the next file. 50.It \&! 51Change the rest in this file without asking, then go on to the next 52file (at which point 53.Nm 54will start asking again). 55.It \&? 56Print out the current filename and ask again. 57.El 58.Pp 59The first two arguments to 60.Nm 61are always the string to replace and 62the string to replace it with. 63The options are as follows: 64.Bl -tag -width "-F filename" -compact -offset indent 65.It Fl w 66The search string is considered as a C symbol; it must be bounded by 67non-symbol characters. 68This option toggles. 69.Pf ( Sq w 70for 71.Sq word . ) 72.It Fl \&! 73.It Fl go 74.It Fl noask 75Enter \&! mode automatically at the beginning of each file. 76.It Fl nogo 77.It Fl ask 78Negate 79.Fl go , 80that is, ask as usual. 81.It Fl c Ns Ar N 82(Where 83.Ar N 84is a number.) 85Give 86.Ar N 87lines of context above and below the 88line with the match when prompting the user. 89.It Fl CA Ns Ar N 90(Where 91.Ar N 92is a number.) 93Give 94.Ar N 95lines of context above the line with the match when prompting the user. 96.It Fl CB Ns Ar N 97(Where 98.Ar N 99is a number.) 100Give 101.Ar N 102lines of context below the line with the match when prompting the user. 103.It Fl f Ar filename 104The 105.Ar filename 106argument is one of the files 107.Nm 108should perform substitutions in. 109.It Fl F Ar filename 110.Nm 111reads 112.Ar filename 113to get the names of files to perform substitutions in. 114The names should appear one to a line. 115.El 116.Pp 117The default amount of context is 118.Fl c2 , 119that is, two lines above and two lines below the line with the match. 120.Pp 121Arguments not beginning with a 122.Fl \& 123sign in the options field are implicitly preceded by 124.Fl f . 125Thus, 126.Fl f 127is really needed only when the file name begins with a 128.Fl \& 129sign. 130.Pp 131.Nm 132reads its options in order and processes files as it gets them. 133This means, for example, that a 134.Fl go 135will affect only files named after the 136.Fl go . 137.Pp 138The most context you can get is ten lines each, above and below. 139.Pp 140.Ar str1 141is limited to 512 characters; there is no limit on the size of 142.Ar str2 . 143Neither one may contain a NUL. 144.Pp 145NULs in the file may cause 146.Nm 147to make various mistakes. 148.Pp 149If any other program modifies the file while 150.Nm 151is running, all 152bets are off. 153.Sh AUTHORS 154.An der Mouse Aq Mt mouse@rodents.montreal.qc.ca 155