Hi,
What is the actual difference between these two? Why the following code works for process substitution and fails for command substitution?
while IFS= read -r line; do echo $line; done < <(cat file)executes successfully and display the contents of the file
But,
while IFS='\n' read -r... (3 Replies)
Hi all,
I have a text file containing sql commands. I want to use sed to replace the " character with the ' character. But when i run the command below it just replaces it with a space? Do i have the escape the ' character if i want to use it?
cat sql.txt
update customer set custid =... (1 Reply)
Can someone help me to write a script / command to read in a file, character by character, replace any unknown ASCII characters with space. then write out the file to a new filename/
Thanks! (1 Reply)
Hi
I have to replace in around 60 files a word an replcae it by another
Suppose all the files have a word intelligent i want to replace it by idiot
I am planning to use sed for executing this job
sed 's/\intelligent/idiot/g'
I plan to have a file (test.txt) which contains... (1 Reply)
Hi All,
I have a big log file i want to delete all characters (between 350th to 450th characters) starting at 350th character position to 450th character position.
please advice or sample code. (6 Replies)
I want to know how to, given a string like W87151WR71C, if the 4th and 5th character (in this case 15) are greater than 45, then to add 1 to the 3rd character (in this case 7) and assign the revised string the variable name MODSTRING.
Thanks in advance. This is ultimately to grab info from... (6 Replies)
Hi Gurus,
I am working with a korn shell script. I should replace in a very great file the character ";" with a space.
Example:
2750;~
2734;~
2778;~
2751;~
2751;~
2752;~
what the fastest method is? Sed? Awk?
Speed is dead main point, Seen the dimensions of the files
Thanks (6 Replies)
I want to get the last character from my machine name using the following code, the default shell is bash, the script runs in ksh.
I get 'bad' substitution error on running the script, but works fine if run using dot and space.
Why?
$ echo $0
bash
$ cat -n myenv.sh
1 ... (8 Replies)
A portion of my input is as follows:
1087 IKON01,49 A WA- -1 . -1 . 0 W WA- -1 . -1 . 0 . -1 . -1 -1 -1 -1 -1 -1 W
1088 IKON01,49 A J.@QU80MW. 2... (2 Replies)
Hi,
Anyone can help using SED searches a character string for a specified delimiter character, and returns a leading or trailing space/blank.
Text file :
"1"|"ExternalClassDEA519CF5"|"Art1"
"2"|"ExternalClass563EA516C"|"Art3"
"3"|"ExternalClass305ED16B8"|"Art9"
...
...
... (2 Replies)
Discussion started by: fspalero
2 Replies
LEARN ABOUT SUSE
getline
GETLINE(3) Linux Programmer's Manual GETLINE(3)NAME
getline, getdelim - delimited string input
SYNOPSIS
#include <stdio.h>
ssize_t getline(char **lineptr, size_t *n, FILE *stream);
ssize_t getdelim(char **lineptr, size_t *n, int delim, FILE *stream);
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
Before glibc 2.10:
getline(), getdelim(): _GNU_SOURCE
Since glibc 2.10:
getline(), getdelim(): _POSIX_C_SOURCE >= 200809L || _XOPEN_SOURCE >= 700
DESCRIPTION
getline() reads an entire line from stream, storing the address of the buffer containing the text into *lineptr. The buffer is null-termi-
nated and includes the newline character, if one was found.
If *lineptr is NULL, then getline() will allocate a buffer for storing the line, which should be freed by the user program. (In this case,
the value in *n is ignored.)
Alternatively, before calling getline(), *lineptr can contain a pointer to a malloc(3)-allocated buffer *n bytes in size. If the buffer is
not large enough to hold the line, getline() resizes it with realloc(3), updating *lineptr and *n as necessary.
In either case, on a successful call, *lineptr and *n will be updated to reflect the buffer address and allocated size respectively.
getdelim() works like getline(), except a line delimiter other than newline can be specified as the delimiter argument. As with getline(),
a delimiter character is not added if one was not present in the input before end of file was reached.
RETURN VALUE
On success, getline() and getdelim() return the number of characters read, including the delimiter character, but not including the termi-
nating null byte. This value can be used to handle embedded null bytes in the line read.
Both functions return -1 on failure to read a line (including end-of-file condition).
ERRORS
EINVAL Bad arguments (n or lineptr is NULL, or stream is not valid).
VERSIONS
These functions are available since libc 4.6.27.
CONFORMING TO
Both getline() and getdelim() were originally GNU extensions. They were standardized in POSIX.1-2008.
EXAMPLE
#define _GNU_SOURCE
#include <stdio.h>
#include <stdlib.h>
int
main(void)
{
FILE *fp;
char *line = NULL;
size_t len = 0;
ssize_t read;
fp = fopen("/etc/motd", "r");
if (fp == NULL)
exit(EXIT_FAILURE);
while ((read = getline(&line, &len, fp)) != -1) {
printf("Retrieved line of length %zu :
", read);
printf("%s", line);
}
free(line);
exit(EXIT_SUCCESS);
}
SEE ALSO read(2), fgets(3), fopen(3), fread(3), gets(3), scanf(3), feature_test_macros(7)COLOPHON
This page is part of release 3.25 of the Linux man-pages project. A description of the project, and information about reporting bugs, can
be found at http://www.kernel.org/doc/man-pages/.
GNU 2010-06-12 GETLINE(3)