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Diffstat (limited to 'patch.1')
| -rw-r--r-- | patch.1 | 248 |
1 files changed, 248 insertions, 0 deletions
@@ -0,0 +1,248 @@ +.Dd 2016-03-20 +.Dt PATCH 1 +.Os patch +.Sh NAME +.Nm patch +.Nd Apply patches to files +.Sh SYNOPSIS +.Nm +.Op Fl c | e | n | u +.Op Fl d Ar dir +.Op Fl D Ar define +.Op Fl o Ar outfile +.Op Fl p Ar num +.Op Fl r Ar rejectfile +.Op Fl bflNRU +.Po +.Fl i Ar patchfile +| < +.Ar patchfile +.Pc +.Op Ar file +.Sh DESCRIPTION +.Nm +applies patches to files from difference listings +produced by +.Xr diff 1 . +.Pp +.Nm +will skip any garbage unless the +.Ar patchfile +consists entirely of garbage. +Garbage is any data that does not conform to +the supported difference listing formats. +.Nm +supports all difference listing formats +specified in +.Xr diff 1p +except for the +.Fl f +flag in +.Xr diff 1p . +.Pp +.Nm +shall figure out which files to patch from the +mentions of filenames in the patch, unless the files +are specified explicitly. As an extension to the +standard, this implementation of +.Nm +can determine the filename by looking at the +\fIdiff\fP-lines that are produced by +.Xr diff 1 +when comparing directories. However, if the +.Ar file +is specified, all patches in the +.Ar patchfile +shall be applied to that +.Ar file . +.Sh OPTIONS +.Bl -tag -width Ds +.It Fl b +Back up files before the first time that a patch +is applied to them. The backups will have the +suffix \fI.orig\fP. +.It Fl c +Treat anything that is not conforming to the +copied context format as garbage. +.It Fl d Ar dir +Prepend +.Ar dir +to all filenames that appear in the patchfile. +.It Fl D Ar define +Mark added lines with the C preprocessor construct +.Bd -literal -offset left + #ifdef \fIdefine\fP + ... + #endif +.Ed + +Mark removed lines with the C preprocessor construct +.Bd -literal -offset left + #ifndef \fIdefine\fP + ... + #endif +.Ed + +Mark changed lines with the C preprocessor construct +.Bd -literal -offset left + #ifdef \fIdefine\fP + ... + #else + ... + #endif +.Ed + +As an extension to the standard, +.Ar define +can be \fI1\fP or \fI0\fP to use +.Bd -literal -offset left + #if 1 + #if 0 +.Ed + +(swap those lines if +.Ar define +is \fI0\fP) instead of +.Bd -literal -offset left + #ifdef \fIdefine\fP + #ifndef \fIdefine\fP +.Ed + +As another extension to the standard, if +.Ar define +begins with an exclamation point (\fB!\fP), +.Bd -literal -offset left + #ifdef \fIdefine\fP + #if 1 +.Ed + +and +.Bd -literal -offset left + #ifndef \fIdefine\fP + #if 0 +.Ed + +are swapped. + +.Nm +does not guarantee that a patched C source +code file will be at least as syntactically +correct after patching as it was before, +despite this being implied by the standard. +The syntactic correctness can be broken +when edits are made on lines split using line +continuation, made in comments, or spanning +CPP conditional directives. +.It Fl e +Treat anything that is not conforming to the +\fIed\fP-script format as garbage. +.It Fl f +Don't ask any questions. +.It Fl i Ar patchfile +Read the +.Ar patchfile +instead of standard output. +.It Fl l +Any sequence of whitespace of at least length 1 +in the input file shall match any sequence +of whitespace of at least length 1 in the +difference script when testing if lines match. +Additionally, any whitespace at the beginning of +a line or at the end of a line is ignored when +matching lines. The former case is an extension +of the standard. +.It Fl n +Treat anything that is not conforming to the +normal format as garbage. +.It Fl N +Ignore already applied hunks. POSIX specifies +that already applied patches shall be ignored +if this flag is used. A hunk is a contiguous +portion of a patch. A patch is a single +file-comparison output from +.Xr diff 1 . +.It Fl o Ar outfile +Store resulting files from patches to +.Ar outfile +instead of to the patched file itself. +If the patchfile patches multiple files, +the results are concatenated. If a patchfile +patches a file multiple times, intermediary +results are also stored. + +As an extension to the standard, you may use +non-regular files such as \fI/dev/stdout\fP +and \fI/dev/null\fP. \fI/dev/null\fP can be +used to perform a dryrun. +.It Fl p Ar num +Remove the first +.Ar num +components from filenames that appear in the +patchfile. Any leading / is regarded as the +first component. If +.Ar num +is 0, the entire filename is used. Without +this flag only basename is used. +.It Fl r Ar rejectfile +Save rejected hunks to +.Ar rejectfile +rather than to the \fIfilename.rej\fP where \fIfilename\fP +is the filename of the file that is being patched. Rejected +hunks are hunks that cannot be applied. + +Unless +.Fl U +is used, rejected hunks are stored in copied +context format. However, the timestamps will +be omitted. +.It Fl R +Try to apply patches reversed before trying +to apply them in normal direction. +.It Fl u +Treat anything that is not conforming to the +unified context format as garbage. +.It Fl U +Store rejected hunks in unified context rather +than copied context. Copied context is the +default even for unified context patches. +.El +.Sh NOTES +Files that become empty as a result of a patch +are not removed. +.Pp +Symbolic links are treated as regular files, +provided that they link to regular files. +.Pp +Timestamps that appear in diff headers are not +applied. +.Pp +Encapsulated patches, and patches with CRLF +line breaks \(em or any other string \(em rather +than LF line breaks are not supported. +.Pp +In this implementation, when the user is prompted, +the message is printed to \fI/dev/tty\fP, rather +than \fI/dev/stdout\fP despite POSIX's mandate. +This is to make it possible to use \fI/dev/stdout\fP +as the output file. +.Pp +Unportable characters in filenames are supported +by parsing them as C string literals. +.Pp +In this implementation, the +.Fl D +flag can be used with \fIed\fP-scripts. +.Sh SEE ALSO +.Xr diff 1 , +.Xr ed 1 +.Sh STANDARDS +The +.Nm +utility is compliant with the +.St -p1003.1-2013 +specification except for the exceptions noted above. +.Pp +The +.Op Fl fU +flags are extensions to that specification, +other extensions are noted above. |