Do terminal, como posso imprimir para produzir uma seção específica do resultado de man something ?
Por exemplo, se eu quisesse obter algumas informações sobre o valor de retorno da função C, eu gostaria de ver algo assim:
RETURN VALUE
On success, the number of bytes written is returned (zero indicates
nothing was written). It is not an error if this number is smaller
than the number of bytes requested; this may happen for example because
the disk device was filled. See also NOTES.
On error, -1 is returned, and errno is set appropriately.
If count is zero and fd refers to a regular file, then write() may
return a failure status if one of the errors below is detected. If no
errors are detected, or error detection is not performed, 0 will be
returned without causing any other effect. If count is zero and fd
refers to a file other than a regular file, the results are not speci‐
fied.
ERRORS
EAGAIN The file descriptor fd refers to a file other than a socket and
has been marked nonblocking (O_NONBLOCK), and the write would
block. See open(2) for further details on the O_NONBLOCK flag.
EAGAIN or EWOULDBLOCK
The file descriptor fd refers to a socket and has been marked
nonblocking (O_NONBLOCK), and the write would block.
[...]
em vez de:
WRITE(2) Linux Programmer's Manual WRITE(2)
NAME
write - write to a file descriptor
SYNOPSIS
#include <unistd.h>
ssize_t write(int fd, const void *buf, size_t count);
DESCRIPTION
write() writes up to count bytes from the buffer pointed buf to the
file referred to by the file descriptor fd.
The number of bytes written may be less than count if, for example,
there is insufficient space on the underlying physical medium, or the
RLIMIT_FSIZE resource limit is encountered (see setrlimit(2)), or the
call was interrupted by a signal handler after having written less than
count bytes. (See also pipe(7).)
For a seekable file (i.e., one to which lseek(2) may be applied, for
example, a regular file) writing takes place at the current file off‐
set, and the file offset is incremented by the number of bytes actually
[...]
Para citar meu próprio post do Meta :
Já tenho um método favorito para isso, sobre o qual você pode ler na página less man em dois lugares:
LESS='+/\+cmd' man less
e
LESS='+/LESS[[:space:]]*Options' man less
(Veja o que eu fiz lá?)
Você pode usar o sinal -P do programa man para usar um pager para exibir páginas. Por exemplo, você pode usar less como o programa pager com o sinalizador -p para procurar o padrão ERROR que acontece no início da linha dentro da página man:
man -P 'less -p ^ERRORS' symlink
Isso abre a página de manual de symlink e pula diretamente para a seção ERRORS dele.
Se você acabou de abrir uma página de manual como:
man cowsay
Você pode então digitar:
/AUTHOR
para encontrar e pular para a linha AUTHOR, por exemplo. Ou: /myFunction
encontrar instâncias de myFunction na manpage.
(Se houver várias instâncias, você pode pressionar n para ir para a próxima instância)
Além disso, se você estiver em uma página man, você pode digitar h e obter um resumo de menos comandos, como abaixo. Eu os cortei depois de partes que achei que eram relevantes para você, mas tem mais.
SUMMARY OF LESS COMMANDS
Commands marked with * may be preceded by a number, N.
Notes in parentheses indicate the behavior if N is given.
h H Display this help.
q :q Q :Q ZZ Exit.
---------------------------------------------------------------------------
MOVING
e ^E j ^N CR * Forward one line (or N lines).
y ^Y k ^K ^P * Backward one line (or N lines).
f ^F ^V SPACE * Forward one window (or N lines).
b ^B ESC-v * Backward one window (or N lines).
z * Forward one window (and set window to N).
w * Backward one window (and set window to N).
ESC-SPACE * Forward one window, but don't stop at end-of-file.
d ^D * Forward one half-window (and set half-window to N).
u ^U * Backward one half-window (and set half-window to N).
ESC-) RightArrow * Left one half screen width (or N positions).
ESC-( LeftArrow * Right one half screen width (or N positions).
F Forward forever; like "tail -f".
r ^R ^L Repaint screen.
R Repaint screen, discarding buffered input.
---------------------------------------------------
Default "window" is the screen height.
Default "half-window" is half of the screen height.
---------------------------------------------------------------------------
SEARCHING
/pattern * Search forward for (N-th) matching line.
?pattern * Search backward for (N-th) matching line.
n * Repeat previous search (for N-th occurrence).
N * Repeat previous search in reverse direction.
ESC-n * Repeat previous search, spanning files.
ESC-N * Repeat previous search, reverse dir. & spanning files.
ESC-u Undo (toggle) search highlighting.
&pattern * Display only matching lines
---------------------------------------------------
Search patterns may be modified by one or more of:
^N or ! Search for NON-matching lines.
^E or * Search multiple files (pass thru END OF FILE).
^F or @ Start search at FIRST file (for /) or last file (for ?).
^K Highlight matches, but don't move (KEEP position).
^R Don't use REGULAR EXPRESSIONS.
---------------------------------------------------------------------------
JUMPING
g ESC-> * Go to last line in file (or line N).
p % * Go to beginning of file (or N percent into file).
Se você quiser ler mais facilmente as páginas do manual, isso deve funcionar.
Tags command-line man