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Diffstat (limited to 'txr.1')
| -rw-r--r-- | txr.1 | 60 |
1 files changed, 59 insertions, 1 deletions
@@ -3582,7 +3582,7 @@ A summary of the available directives follows: .coIP @(eof) Explicitly match the end of file. Fails if unmatched data remains in -the input stream. +the input stream. Can capture or match the termination status of a pipe. .coIP @(eol) Explicitly match the end of line. Fails if the current position is not the @@ -5008,6 +5008,64 @@ lines: @(do (tprint remainder)) .brev +.dir eof + +The +.code eof +directive, if not given any argument, matches successfully when no more input +is available from the current input source. + +In the following example, the +.meta line +variable captures the text +.str "One-line file" +and then since that is the last line of input, the +.code eof +directive matches: + +.IP code: +.mono +\ @line + @(eof) +.onom + +.IP data: +.mono +\ One-line file +.onom +.PP + +If the data consisted of two or more lines, +.code eof +would fail. + +The +.code eof +directive may be given a single argument, which is a pattern that matches the +termination status of the input source. This is useful when the input source +is a process pipe. For the purposes of +.codn eof , +sources which are not process pipes have the symbol +.code t +as their termination status. + +In the following example, which assumes the availability of a POSIX shell +command interpreter in the host system, the variable +.meta a +captures the string +.str a +and the +.meta status +variable captures the integer value +.codn 5 , +which is the termination status of the command: + +.verb + @(next (open-command "echo a; exit 5")) + @a + @(eof status) +.brev + .dirs some all none maybe cases choose These directives, called the parallel directives, combine multiple subqueries, |